Error detection for a wireless channel

ABSTRACT

Methods, systems, and devices for wireless communications are described. In some systems, a first device may transmit a signal to a second device including a number of error detection bits interleaved with a number of information bits. The second device may use the error detection bits to determine if the signal was received correctly, where each error detection bit may be associated with a set of information bits. The second device may progressively decode the signal and continuously perform an error detection calculation based on a first set of information bits associated with a first error detection bit. Based on the error detection calculation, the second device may calculate an expected error detection bit corresponding to the first error detection bit. The second device may compare the first error detection bit to the expected error detection bit. Other aspects and features are also claimed and described.

FIELD OF TECHNOLOGY

The following relates generally to wireless communications and morespecifically to error detection method for a wireless channel. Variousembodiments enable and provide techniques to aid in reducing decodinglatency and/or opportunistically halting decode operations.

BACKGROUND

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal frequency division multiple access (OFDMA), or discreteFourier transform spread orthogonal frequency division multiplexing(DFT-S-OFDM). A wireless multiple-access communications system mayinclude one or more base stations or one or more network access nodes,each simultaneously supporting communication for multiple communicationdevices, which may be otherwise known as user equipment (UE).

In some wireless communications systems, a first device may transmit asignal including a number of information bits to a second device via acommunication channel. The signal may also include a number of errordetection bits associated with the information bits, which the seconddevice may use to determine if the signal was received correctly. Insome cases, the first device may interleave and encode the signal priorto transmitting the signal to the second device. The second device mayreceive the signal and perform an error check to determine if the signalwas received correctly. In some cases, current techniques for performingerror checks may be inefficient and result in long decoding operationsat the second device.

SUMMARY

The described techniques relate to improved methods, systems, devices,and apparatuses that support error detection method for a wirelesschannel. Generally, the described techniques provide for efficient earlyterminations of a decoding operation of a received signal. In someexamples, a first device may transmit a signal to a second device, thesignal may include a quantity of information values (e.g., payload bits)and a quantity of error detection values (e.g., parity bits). Prior totransmission, the first device may interleave the error detection valueswith the information values such that the number of error detectionvalues are spread throughout the signal. In addition, in some examples,prior to transmission, the first device may encode the interleaved datausing a polar code. In some cases, the first device may encode theinterleaved signal and transmit the signal to the second device, whichmay decode and de-interleave the signal.

In some implementations of the present disclosure, the second device mayreceive (e.g., decode and deinterleave) a first set of the number ofinformation values and may calculate an expected error detection valuebased on the first set of information values. In some aspects, thesecond device may perform an error check on the signal (e.g., on thefirst set of information values included in the signal). Based onperforming the error check, the second device may compare the expectederror detection value to an error detection value that is received inthe signal (e.g., and that is associated with the first set ofinformation values). In some examples, the second device may determinethat the value associated with the expected error detection value isdifferent than the received error detection value. Accordingly, in suchexamples, the second device may determine that the first set ofinformation values in the signal were received incorrectly and may stopdecoding the signal (e.g., terminate a decoding operation associatedwith receiving the signal). The techniques for doing error detectionbased early termination of decoding may be configured to work withsignals that are associated with successive cancelation decoding, suchas polar decoding.

A method of wireless communication is described. The method may includereceiving a signal that includes a set of error detection values and aset of information values, determining a coefficient, the coefficientassociated with a first information value of the set of informationvalues, configured for determining at least one error detection value,determining a first error detection value based on the coefficientassociated with the first information value, determining that a seconderror detection value received in the signal and associated with thefirst information value is different than the first error detectionvalue, and terminating decoding of the signal based on the first errordetection value and the second error detection value.

An apparatus for wireless communication is described. The apparatus mayinclude a processor, memory coupled with the processor, and instructionsstored in the memory. The instructions may be executable by theprocessor to cause the apparatus to receive a signal that includes a setof error detection values and a set of information values, determine acoefficient, the coefficient associated with a first information valueof the set of information values, configured for determining at leastone error detection value, determine a first error detection value basedon the coefficient associated with the first information value,determine that a second error detection value received in the signal andassociated with the first information value is different than the firsterror detection value, and terminate decoding of the signal based on thefirst error detection value and the second error detection value.

Another apparatus for wireless communication is described. The apparatusmay include means for receiving a signal that includes a set of errordetection values and a set of information values, determining acoefficient, the coefficient associated with a first information valueof the set of information values, configured for determining at leastone error detection value, determining a first error detection valuebased on the coefficient associated with the first information value,determining that a second error detection value received in the signaland associated with the first information value is different than thefirst error detection value, and terminating decoding of the signalbased on the first error detection value and the second error detectionvalue.

A non-transitory computer-readable medium storing code for wirelesscommunication is described. The code may include instructions executableby a processor to receive a signal that includes a set of errordetection values and a set of information values, determine acoefficient, the coefficient associated with a first information valueof the set of information values, configured for determining at leastone error detection value, determine a first error detection value basedon the coefficient associated with the first information value,determine that a second error detection value received in the signal andassociated with the first information value is different than the firsterror detection value, and terminate decoding of the signal based on thefirst error detection value and the second error detection value.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining an indexvalue associated with the first information value based on receiving thesignal, where determining the coefficient may be based on determiningthe index value.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, determining the coefficientfurther may include operations, features, means, or instructions forretrieving the coefficient from a memory based on the determined indexvalue.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, determining the coefficientfurther may include operations, features, means, or instructions fordetermining a second index value and a third index value based on theindex value associated with the first information value, and retrievinga value from a memory based on the second index value, where thecoefficient may be determined based on the value retrieved from thememory and the third index value.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for applying a divisionoperation using a second value to the index value to generate the secondindex value, where determining the second index value may be based onapplying the division operation, and applying a modulo operation usingthe second value to the index value to generate the third index value,where determining the third index value may be based on applying themodulo operation.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the memory stores adown-sampled set of coefficients associated with the set of informationvalues.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for decoding the signalusing a polar code to identify the first information value of the set ofinformation values and the second error detection value of the set oferror detection values included in the signal based on receiving thesignal, where determining the coefficient may be based on decoding thesignal using the polar code.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for deinterleaving thesecond error detection value from the set of information values of thesignal based on decoding the signal using the polar code.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for entering a lower powermode of the user equipment based on terminating the decoding.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the lower power mode may be amicro-sleep mode of the user equipment.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for applying an identifiermask to the first error detection value, where determining that thefirst error detection value may be different than the second errordetection value may be based on applying the identifier mask to thefirst error detection value.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for applying a set ofidentifier masks to the first error detection value to generate a set ofcandidate values, respectively, and comparing each value of the set ofcandidate values to the second error detection value, where determiningthat the first error detection value may be different than the seconderror detection value may be based on comparing each value of the set ofcandidate values to the second error detection value.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for accumulating one ormore information values and one or more coefficients, where determiningthe first error detection value may be based on accumulating the set ofinformation values and the one or more coefficients.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a set ofinformation values of the signal associated with the second errordetection value based on receiving the signal, where the set ofinformation values includes the first information value, and determininga set of coefficients, each coefficient of the set of coefficientsassociated with an information value of the set of information valuesbased on identifying the set of information values, where determiningthe first error detection value may be based on the set of coefficientsand the set of information values.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for comparing the firsterror detection value with the second error detection value, wheredetermining that the first error detection value may be different thanthe second error detection value may be based on comparing the firsterror detection value with the second error detection value.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, an error detection value mayinclude an error detection bit and an information value may include aninformation bit.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first error detectionvalue may be determined using the coefficient and the first informationvalue.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the set of error detectionvalues may be interleaved with the set of information values.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationsthat supports error detection for a wireless channel in accordance withaspects of the present disclosure.

FIG. 2 illustrates an example of a wireless communications system thatsupports error detection for a wireless channel in accordance withaspects of the present disclosure.

FIG. 3 illustrates an example of a process flow that supports errordetection for a wireless channel in accordance with aspects of thepresent disclosure.

FIG. 4 illustrates an example of a process flow that supports errordetection for a wireless channel in accordance with aspects of thepresent disclosure.

FIG. 5 illustrates an example of a circuit that supports error detectionfor a wireless channel in accordance with aspects of the presentdisclosure.

FIG. 6 illustrates an example of a circuit that supports error detectionfor a wireless channel in accordance with aspects of the presentdisclosure.

FIGS. 7 and 8 show block diagrams of devices that support errordetection for a wireless channel in accordance with aspects of thepresent disclosure.

FIG. 9 shows a block diagram of a communications manager that supportserror detection for a wireless channel in accordance with aspects of thepresent disclosure.

FIG. 10 shows a diagram of a system including a device that supportserror detection for a wireless channel in accordance with aspects of thepresent disclosure.

FIGS. 11 through 14 show flowcharts illustrating methods that supporterror detection for a wireless channel in accordance with aspects of thepresent disclosure.

DETAILED DESCRIPTION

Various implementations relate generally to efficient error detectionmethods for a wireless channel. Some implementations more specificallyrelate to progressively performing error detection of a signal such thata receiving device may determine if the signal is received correctlywith lower latency. In some implementations, a first device may transmita signal in a communication channel (e.g., a downlink control channel)including a number of error detection values or bits (e.g., parity bits)interleaved with a number of information values or bits (e.g., payloadbits). In some cases, the first device may encode the signal with apolar code prior to transmitting the signal to a second device. Thesecond device may receive the signal in the communication channel andmay decode (e.g., polar decode) and deinterleave the signal as part of adecoding operation of the signal. In some instances, the use of polarcodes can prevent some early termination procedures because the polarcode may cause the receiving device to receive the entire signal beforeerror detection procedures may be performed. Techniques are describedherein to enable early-termination of decoding based on error detection(e.g., cyclic redundancy check (CRC) procedure) on signals that areencoded. Encoded signals may be encoded via a polar code as well asother encoding techniques.

In some cases, each error detection bit of the number of error detectionbits may be associated with a subset of the number of information bits.For example, the second device may determine if a subset of the numberof information bits is received correctly based on the error detectionbit associated with the subset of information bits. In someimplementations, the second device may perform an error check based onthe subset of information bits and the error detection bit associatedwith the subset of information bits. For example, the second device maydetermine (e.g., calculate) an expected error detection bit based on thesubset of information bits and may compare the calculated errordetection bit to the error detection bit received in the signal todetermine if the error check passes or fails. If the subset ofinformation bits were correctly received, the calculated error detectionbit may match (e.g., be the same as) the error detection bit received inthe signal. Otherwise, one or more of the subset of information bits mayhave been received incorrectly.

The second device may progressively calculate error detection bits asthe signal is received. For example, the second device may receive afirst set of information bits and may continuously perform an errordetection computation (e.g., or continuously update an error detectioncomputation) associated with determining an expected error detection bitas the first set of information bits are received. The expected errordetection bit may be an error detection that the second device mayexpect to receive if the first set of information bits were receivedcorrectly. The second device may use the expected error detection bit todetermine whether an error associated with the first set of informationbits passes or fails an error check. For instance, the second device maycompare the expected error detection bit to an error detection bit thatthe second device received in the signal to determine if the first setof information bits were received correctly.

In some examples, the second device may determine that the expectederror detection bit is different than the error detection bit receivedin the signal. In such examples, the second device may determine thatone or more information bits of the first set of information bits werereceived incorrectly (e.g., and therefore that the entire signal may beincorrect or corrupt). Accordingly, the second device may terminate thedecoding operation associated with receiving the signal. In someaspects, the second device may terminate the decoding operation prior todecoding the entire signal.

Particular implementations of the subject matter described in thisdisclosure can be implemented to realize one or more of the followingpotential advantages. In some implementations, the described techniquescan enable CRC-based early-termination of decoding a signal that wasencoded using a polar code. In some implementations, the describedtechniques can be used to reduce latency for decoding a signal ascompared to error detection methods that perform error detection afteran entire signal has been received. For example, a device may receive asignal and progressively perform error detection computations associatedwith the signal as the signal is received. As such, the device maydetermine that an error exists in the polar encoded signal prior todecoding the entire signal and the device may terminate the decodingoperation early, which may result in fewer decoding cycles compared toerror detection methods that decode the entire signal prior toperforming an error check. This may enable the device to power off oneor more processing units associated with receiving or decoding a signaland to spend a longer duration in a sleep mode (e.g., a micro sleepmode). In such examples, the device may reduce power consumption andimprove battery life. In some implementations, progressively performingerror checks on a signal may reduce latency even in cases when thesignal is correctly received. For example, a device progressivelyperforming error checks may finish an error check associated with alastly received error detection bit at approximately the same time asthe last error detection bit is received, while a legacy device mayperform an error check for each of a number of error detection bits thatwere received in the signal after receiving the lastly received errordetection bit. As such, a first device implementing aspects of thepresent disclosure may repurpose one or more processing units to adifferent processing task before the legacy device completes its errorcheck procedure, which may result in increased processing capability andefficiency of the first device.

Aspects of the disclosure are initially described in the context ofwireless communications systems. Additionally, aspects of the disclosureare described in the context of process flows and circuitry. Aspects ofthe disclosure are further illustrated by and described with referenceto apparatus diagrams, system diagrams, and flowcharts that relate toerror detection method for a wireless channel.

FIG. 1 illustrates an example of a wireless communications system 100that supports error detection for a wireless channel in accordance withaspects of the present disclosure, in particular of any of the followingexamples. The wireless communications system 100 may include one or morebase stations 105, one or more UEs 115, and a core network 130. In someexamples, the wireless communications system 100 may be a Long TermEvolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-A Pronetwork, or a New Radio (NR) network. In some examples, the wirelesscommunications system 100 may support enhanced broadband communications,ultra-reliable (e.g., mission critical) communications, low latencycommunications, communications with low-cost and low-complexity devices,or any combination thereof.

The base stations 105 may be dispersed throughout a geographic area toform the wireless communications system 100 and may be devices indifferent forms or having different capabilities. The base stations 105and the UEs 115 may wirelessly communicate via one or more communicationlinks 125. Each base station 105 may provide a coverage area 110 overwhich the UEs 115 and the base station 105 may establish one or morecommunication links 125. The coverage area 110 may be an example of ageographic area over which a base station 105 and a UE 115 may supportthe communication of signals according to one or more radio accesstechnologies.

The UEs 115 may be dispersed throughout a coverage area 110 of thewireless communications system 100, and each UE 115 may be stationary,or mobile, or both at different times. The UEs 115 may be devices indifferent forms or having different capabilities. Some example UEs 115are illustrated in FIG. 1. The UEs 115 described herein may be able tocommunicate with various types of devices, such as other UEs 115, thebase stations 105, or network equipment (e.g., core network nodes, relaydevices, integrated access and backhaul (IAB) nodes, or other networkequipment), as shown in FIG. 1.

The base stations 105 may communicate with the core network 130, or withone another, or both. For example, the base stations 105 may interfacewith the core network 130 through one or more backhaul links 120 (e.g.,via an S1, N2, N3, or other interface). The base stations 105 maycommunicate with one another over the backhaul links 120 (e.g., via anX2, Xn, or other interface) either directly (e.g., directly between basestations 105), or indirectly (e.g., via core network 130), or both. Insome examples, the backhaul links 120 may be or include one or morewireless links.

One or more of the base stations 105 described herein may include or maybe referred to by a person having ordinary skill in the art as a basetransceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a next-generation NodeB or agiga-NodeB (either of which may be referred to as a gNB), a Home NodeB,a Home eNodeB, or other suitable terminology.

A UE 115 may include or may be referred to as a mobile device, awireless device, a remote device, a handheld device, or a subscriberdevice, or some other suitable terminology, where the “device” may alsobe referred to as a unit, a station, a terminal, or a client, amongother examples. A UE 115 may also include or may be referred to as apersonal electronic device such as a cellular phone, a personal digitalassistant (PDA), a tablet computer, a laptop computer, or a personalcomputer. In some examples, a UE 115 may include or be referred to as awireless local loop (WLL) station, an Internet of Things (IoT) device,an Internet of Everything (IoE) device, or a machine type communications(MTC) device, among other examples, which may be implemented in variousobjects such as appliances, or vehicles, meters, among other examples.

The UEs 115 described herein may be able to communicate with varioustypes of devices, such as other UEs 115 that may sometimes act as relaysas well as the base stations 105 and the network equipment includingmacro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations,among other examples, as shown in FIG. 1.

The UEs 115 and the base stations 105 may wirelessly communicate withone another via one or more communication links 125 over one or morecarriers. The term “carrier” may refer to a set of radio frequencyspectrum resources having a defined physical layer structure forsupporting the communication links 125. For example, a carrier used fora communication link 125 may include a portion of a radio frequencyspectrum band (e.g., a bandwidth part (BWP)) that is operated accordingto one or more physical layer channels for a given radio accesstechnology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layerchannel may carry acquisition signaling (e.g., synchronization signals,system information), control signaling that coordinates operation forthe carrier, user data, or other signaling. The wireless communicationssystem 100 may support communication with a UE 115 using carrieraggregation or multi-carrier operation. A UE 115 may be configured withmultiple downlink component carriers and one or more uplink componentcarriers according to a carrier aggregation configuration. Carrieraggregation may be used with both frequency division duplexing (FDD) andtime division duplexing (TDD) component carriers.

In some examples (e.g., in a carrier aggregation configuration), acarrier may also have acquisition signaling or control signaling thatcoordinates operations for other carriers. A carrier may be associatedwith a frequency channel (e.g., an evolved universal mobiletelecommunication system terrestrial radio access (E-UTRA) absoluteradio frequency channel number (EARFCN)) and may be positioned accordingto a channel raster for discovery by the UEs 115. A carrier may beoperated in a standalone mode where initial acquisition and connectionmay be conducted by the UEs 115 via the carrier, or the carrier may beoperated in a non-standalone mode where a connection is anchored using adifferent carrier (e.g., of the same or a different radio accesstechnology).

The communication links 125 shown in the wireless communications system100 may include uplink transmissions from a UE 115 to a base station105, or downlink transmissions from a base station 105 to a UE 115.Carriers may carry downlink or uplink communications (e.g., in an FDDmode) or may be configured to carry downlink and uplink communications(e.g., in a TDD mode).

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum, and in some examples the carrier bandwidth may bereferred to as a “system bandwidth” of the carrier or the wirelesscommunications system 100. For example, the carrier bandwidth may be oneof a number of determined bandwidths for carriers of a particular radioaccess technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 megahertz(MHz)). Devices of the wireless communications system 100 (e.g., thebase stations 105, the UEs 115, or both) may have hardwareconfigurations that support communications over a particular carrierbandwidth or may be configurable to support communications over one of aset of carrier bandwidths. In some examples, the wireless communicationssystem 100 may include base stations 105 or UEs 115 that supportsimultaneous communications via carriers associated with multiplecarrier bandwidths. In some examples, each served UE 115 may beconfigured for operating over portions (e.g., a sub-band, a BWP) or allof a carrier bandwidth.

Signal waveforms transmitted over a carrier may be made up of multiplesubcarriers (e.g., using multi-carrier modulation (MCM) techniques suchas orthogonal frequency division multiplexing (OFDM) or discrete Fouriertransform spread OFDM (DFT-S-OFDM)). In a system employing MCMtechniques, a resource element may consist of one symbol period (e.g., aduration of one modulation symbol) and one subcarrier, where the symbolperiod and subcarrier spacing are inversely related. The number of bitscarried by each resource element may depend on the modulation scheme(e.g., the order of the modulation scheme, the coding rate of themodulation scheme, or both). Thus, the more resource elements that a UE115 receives and the higher the order of the modulation scheme, thehigher the data rate may be for the UE 115. A wireless communicationsresource may refer to a combination of a radio frequency spectrumresource, a time resource, and a spatial resource (e.g., spatial layersor beams), and the use of multiple spatial layers may further increasethe data rate or data integrity for communications with a UE 115.

One or more numerologies for a carrier may be supported, where anumerology may include a subcarrier spacing (Δf) and a cyclic prefix. Acarrier may be divided into one or more BWPs having the same ordifferent numerologies. In some examples, a UE 115 may be configuredwith multiple BWPs. In some examples, a single BWP for a carrier may beactive at a given time and communications for the UE 115 may berestricted to one or more active BWPs.

The time intervals for the base stations 105 or the UEs 115 may beexpressed in multiples of a basic time unit which may, for example,refer to a sampling period of T_(s)=1/(Δf_(max)·N_(f)) seconds, whereΔf_(max) may represent the maximum supported subcarrier spacing, andN_(f) may represent the maximum supported discrete Fourier transform(DFT) size. Time intervals of a communications resource may be organizedaccording to radio frames each having a specified duration (e.g., 10milliseconds (ms)). Each radio frame may be identified by a system framenumber (SFN) (e.g., ranging from 0 to 1023).

Each frame may include multiple consecutively numbered subframes orslots, and each subframe or slot may have the same duration. In someexamples, a frame may be divided (e.g., in the time domain) intosubframes, and each subframe may be further divided into a number ofslots. Alternatively, each frame may include a variable number of slots,and the number of slots may depend on subcarrier spacing. Each slot mayinclude a number of symbol periods (e.g., depending on the length of thecyclic prefix prepended to each symbol period). In some wirelesscommunications systems 100, a slot may further be divided into multiplemini-slots containing one or more symbols. Excluding the cyclic prefix,each symbol period may contain one or more (e.g., N_(f)) samplingperiods. The duration of a symbol period may depend on the subcarrierspacing or frequency band of operation.

A subframe, a slot, a mini-slot, or a symbol may be the smallestscheduling unit (e.g., in the time domain) of the wirelesscommunications system 100 and may be referred to as a transmission timeinterval (TTI). In some examples, the TTI duration (e.g., the number ofsymbol periods in a TTI) may be variable. Additionally or alternatively,the smallest scheduling unit of the wireless communications system 100may be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs)).

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using one or more oftime division multiplexing (TDM) techniques, frequency divisionmultiplexing (FDM) techniques, or hybrid TDM-FDM techniques. A controlregion (e.g., a control resource set (CORESET)) for a physical controlchannel may be defined by a number of symbol periods and may extendacross the system bandwidth or a subset of the system bandwidth of thecarrier. One or more control regions (e.g., CORESETs) may be configuredfor a set of the UEs 115. For example, one or more of the UEs 115 maymonitor or search control regions for control information according toone or more search space sets, and each search space set may include oneor multiple control channel candidates in one or more aggregation levelsarranged in a cascaded manner. An aggregation level for a controlchannel candidate may refer to a number of control channel resources(e.g., control channel elements (CCEs)) associated with encodedinformation for a control information format having a given payloadsize. Search space sets may include common search space sets configuredfor sending control information to multiple UEs 115 and UE-specificsearch space sets for sending control information to a specific UE 115.

Each base station 105 may provide communication coverage via one or morecells, for example a macro cell, a small cell, a hot spot, or othertypes of cells, or any combination thereof. The term “cell” may refer toa logical communication entity used for communication with a basestation 105 (e.g., over a carrier) and may be associated with anidentifier for distinguishing neighboring cells (e.g., a physical cellidentifier (PCID), a virtual cell identifier (VCID), or others). In someexamples, a cell may also refer to a geographic coverage area 110 or aportion of a geographic coverage area 110 (e.g., a sector) over whichthe logical communication entity operates. Such cells may range fromsmaller areas (e.g., a structure, a subset of structure) to larger areasdepending on various factors such as the capabilities of the basestation 105. For example, a cell may be or include a building, a subsetof a building, or exterior spaces between or overlapping with geographiccoverage areas 110, among other examples.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by theUEs 115 with service subscriptions with the network provider supportingthe macro cell. A small cell may be associated with a lower-powered basestation 105, as compared with a macro cell, and a small cell may operatein the same or different (e.g., licensed, unlicensed) frequency bands asmacro cells. Small cells may provide unrestricted access to the UEs 115with service subscriptions with the network provider or may providerestricted access to the UEs 115 having an association with the smallcell (e.g., the UEs 115 in a closed subscriber group (CSG), the UEs 115associated with users in a home or office). A base station 105 maysupport one or multiple cells and may also support communications overthe one or more cells using one or multiple component carriers.

In some examples, a carrier may support multiple cells, and differentcells may be configured according to different protocol types (e.g.,MTC, narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB)) that mayprovide access for different types of devices.

In some examples, a base station 105 may be movable and thereforeprovide communication coverage for a moving geographic coverage area110. In some examples, different geographic coverage areas 110associated with different technologies may overlap, but the differentgeographic coverage areas 110 may be supported by the same base station105. In other examples, the overlapping geographic coverage areas 110associated with different technologies may be supported by differentbase stations 105. The wireless communications system 100 may include,for example, a heterogeneous network in which different types of thebase stations 105 provide coverage for various geographic coverage areas110 using the same or different radio access technologies.

The wireless communications system 100 may support synchronous orasynchronous operation. For synchronous operation, the base stations 105may have similar frame timings, and transmissions from different basestations 105 may be approximately aligned in time. For asynchronousoperation, the base stations 105 may have different frame timings, andtransmissions from different base stations 105 may, in some examples,not be aligned in time. The techniques described herein may be used foreither synchronous or asynchronous operations.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay such information to acentral server or application program that makes use of the informationor presents the information to humans interacting with the applicationprogram. Some UEs 115 may be designed to collect information or enableautomated behavior of machines or other devices. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples,half-duplex communications may be performed at a reduced peak rate.Other power conservation techniques for the UEs 115 include entering apower saving deep sleep mode when not engaging in active communications,operating over a limited bandwidth (e.g., according to narrowbandcommunications), or a combination of these techniques. For example, someUEs 115 may be configured for operation using a narrowband protocol typethat is associated with a defined portion or range (e.g., set ofsubcarriers or resource blocks (RBs)) within a carrier, within aguard-band of a carrier, or outside of a carrier.

The wireless communications system 100 may be configured to supportultra-reliable communications or low-latency communications, or variouscombinations thereof. For example, the wireless communications system100 may be configured to support ultra-reliable low-latencycommunications (URLLC) or mission critical communications. The UEs 115may be designed to support ultra-reliable, low-latency, or criticalfunctions (e.g., mission critical functions). Ultra-reliablecommunications may include private communication or group communicationand may be supported by one or more mission critical services such asmission critical push-to-talk (MCPTT), mission critical video (MCVideo),or mission critical data (MCData). Support for mission criticalfunctions may include prioritization of services, and mission criticalservices may be used for public safety or general commercialapplications. The terms ultra-reliable, low-latency, mission critical,and ultra-reliable low-latency may be used interchangeably herein.

In some examples, a UE 115 may also be able to communicate directly withother UEs 115 over a device-to-device (D2D) communication link 135(e.g., using a peer-to-peer (P2P) or D2D protocol). One or more UEs 115utilizing D2D communications may be within the geographic coverage area110 of a base station 105. Other UEs 115 in such a group may be outsidethe geographic coverage area 110 of a base station 105 or be otherwiseunable to receive transmissions from a base station 105. In someexamples, groups of the UEs 115 communicating via D2D communications mayutilize a one-to-many (1:M) system in which each UE 115 transmits toevery other UE 115 in the group. In some examples, a base station 105facilitates the scheduling of resources for D2D communications. In othercases, D2D communications are carried out between the UEs 115 withoutthe involvement of a base station 105.

In some systems, the D2D communication link 135 may be an example of acommunication channel, such as a sidelink communication channel, betweenvehicles (e.g., UEs 115). In some examples, vehicles may communicateusing vehicle-to-everything (V2X) communications, vehicle-to-vehicle(V2V) communications, or some combination of these. A vehicle may signalinformation related to traffic conditions, signal scheduling, weather,safety, emergencies, or any other information relevant to a V2X system.In some examples, vehicles in a V2X system may communicate with roadsideinfrastructure, such as roadside units, or with the network via one ormore network nodes (e.g., base stations 105) using vehicle-to-network(V2N) communications, or with both.

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC) or 5G core (5GC), which may include at leastone control plane entity that manages access and mobility (e.g., amobility management entity (MME), an access and mobility managementfunction (AMF)) and at least one user plane entity that routes packetsor interconnects to external networks (e.g., a serving gateway (S-GW), aPacket Data Network (PDN) gateway (P-GW), or a user plane function(UPF)). The control plane entity may manage non-access stratum (NAS)functions such as mobility, authentication, and bearer management forthe UEs 115 served by the base stations 105 associated with the corenetwork 130. User IP packets may be transferred through the user planeentity, which may provide IP address allocation as well as otherfunctions. The user plane entity may be connected to the networkoperators IP services 150. The operators IP services 150 may includeaccess to the Internet, Intranet(s), an IP Multimedia Subsystem (IMS),or a Packet-Switched Streaming Service.

Some of the network devices, such as a base station 105, may includesubcomponents such as an access network entity 140, which may be anexample of an access node controller (ANC). Each access network entity140 may communicate with the UEs 115 through one or more other accessnetwork transmission entities 145, which may be referred to as radioheads, smart radio heads, or transmission/reception points (TRPs). Eachaccess network transmission entity 145 may include one or more antennapanels. In some configurations, various functions of each access networkentity 140 or base station 105 may be distributed across various networkdevices (e.g., radio heads and ANCs) or consolidated into a singlenetwork device (e.g., a base station 105).

The wireless communications system 100 may operate using one or morefrequency bands, typically in the range of 300 megahertz (MHz) to 300gigahertz (GHz). Generally, the region from 300 MHz to 3 GHz is known asthe ultra-high frequency (UHF) region or decimeter band because thewavelengths range from approximately one decimeter to one meter inlength. The UHF waves may be blocked or redirected by buildings andenvironmental features, but the waves may penetrate structuressufficiently for a macro cell to provide service to the UEs 115 locatedindoors. The transmission of UHF waves may be associated with smallerantennas and shorter ranges (e.g., less than 100 kilometers) compared totransmission using the smaller frequencies and longer waves of the highfrequency (ff) or very high frequency (VHF) portion of the spectrumbelow 300 MHz.

The wireless communications system 100 may also operate in a super highfrequency (SHF) region using frequency bands from 3 GHz to 30 GHz, alsoknown as the centimeter band, or in an extremely high frequency (EHF)region of the spectrum (e.g., from 30 GHz to 300 GHz), also known as themillimeter band. In some examples, the wireless communications system100 may support millimeter wave (mmW) communications between the UEs 115and the base stations 105, and EHF antennas of the respective devicesmay be smaller and more closely spaced than UHF antennas. In someexamples, this may facilitate use of antenna arrays within a device. Thepropagation of EHF transmissions, however, may be subject to evengreater atmospheric attenuation and shorter range than SHF or UHFtransmissions. The techniques disclosed herein may be employed acrosstransmissions that use one or more different frequency regions, anddesignated use of bands across these frequency regions may differ bycountry or regulating body.

The wireless communications system 100 may utilize both licensed andunlicensed radio frequency spectrum bands. For example, the wirelesscommunications system 100 may employ License Assisted Access (LAA),LTE-Unlicensed (LTE-U) radio access technology, or NR technology in anunlicensed band such as the 5 GHz industrial, scientific, and medical(ISM) band. When operating in unlicensed radio frequency spectrum bands,devices such as the base stations 105 and the UEs 115 may employ carriersensing for collision detection and avoidance. In some examples,operations in unlicensed bands may be based on a carrier aggregationconfiguration in conjunction with component carriers operating in alicensed band (e.g., LAA). Operations in unlicensed spectrum may includedownlink transmissions, uplink transmissions, P2P transmissions, or D2Dtransmissions, among other examples.

A base station 105 or a UE 115 may be equipped with multiple antennas,which may be used to employ techniques such as transmit diversity,receive diversity, multiple-input multiple-output (MIMO) communications,or beamforming. The antennas of a base station 105 or a UE 115 may belocated within one or more antenna arrays or antenna panels, which maysupport MIMO operations or transmit or receive beamforming. For example,one or more base station antennas or antenna arrays may be co-located atan antenna assembly, such as an antenna tower. In some examples,antennas or antenna arrays associated with a base station 105 may belocated in diverse geographic locations. A base station 105 may have anantenna array with a number of rows and columns of antenna ports thatthe base station 105 may use to support beamforming of communicationswith a UE 115. Likewise, a UE 115 may have one or more antenna arraysthat may support various MIMO or beamforming operations. Additionally oralternatively, an antenna panel may support radio frequency beamformingfor a signal transmitted via an antenna port.

The base stations 105 or the UEs 115 may use MIMO communications toexploit multipath signal propagation and increase the spectralefficiency by transmitting or receiving multiple signals via differentspatial layers. Such techniques may be referred to as spatialmultiplexing. The multiple signals may, for example, be transmitted bythe transmitting device via different antennas or different combinationsof antennas. Likewise, the multiple signals may be received by thereceiving device via different antennas or different combinations ofantennas. Each of the multiple signals may be referred to as a separatespatial stream and may carry bits associated with the same data stream(e.g., the same codeword) or different data streams (e.g., differentcodewords). Different spatial layers may be associated with differentantenna ports used for channel measurement and reporting. MIMOtechniques include single-user MIMO (SU-MIMO), where multiple spatiallayers are transmitted to the same receiving device, and multiple-userMIMO (MU-MIMO), where multiple spatial layers are transmitted tomultiple devices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105, a UE 115) to shape or steeran antenna beam (e.g., a transmit beam, a receive beam) along a spatialpath between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that some signals propagatingat particular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying amplitude offsets, phase offsets, or both to signals carriedvia the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

A base station 105 or a UE 115 may use beam sweeping techniques as partof beam forming operations. For example, a base station 105 may usemultiple antennas or antenna arrays (e.g., antenna panels) to conductbeamforming operations for directional communications with a UE 115.Some signals (e.g., synchronization signals, reference signals, beamselection signals, or other control signals) may be transmitted by abase station 105 multiple times in different directions. For example,the base station 105 may transmit a signal according to differentbeamforming weight sets associated with different directions oftransmission. Transmissions in different beam directions may be used toidentify (e.g., by a transmitting device, such as a base station 105, orby a receiving device, such as a UE 115) a beam direction for latertransmission or reception by the base station 105.

Some signals, such as data signals associated with a particularreceiving device, may be transmitted by a base station 105 in a singlebeam direction (e.g., a direction associated with the receiving device,such as a UE 115). In some examples, the beam direction associated withtransmissions along a single beam direction may be determined based on asignal that was transmitted in one or more beam directions. For example,a UE 115 may receive one or more of the signals transmitted by the basestation 105 in different directions and may report to the base station105 an indication of the signal that the UE 115 received with a highestsignal quality or an otherwise acceptable signal quality.

In some examples, transmissions by a device (e.g., by a base station 105or a UE 115) may be performed using multiple beam directions, and thedevice may use a combination of digital precoding or radio frequencybeamforming to generate a combined beam for transmission (e.g., from abase station 105 to a UE 115). The UE 115 may report feedback thatindicates precoding weights for one or more beam directions, and thefeedback may correspond to a configured number of beams across a systembandwidth or one or more sub-bands. The base station 105 may transmit areference signal (e.g., a cell-specific reference signal (CRS), achannel state information reference signal (CSI-RS)), which may beprecoded or unprecoded. The UE 115 may provide feedback for beamselection, which may be a precoding matrix indicator (PMI) orcodebook-based feedback (e.g., a multi-panel type codebook, a linearcombination type codebook, a port selection type codebook). Althoughthese techniques are described with reference to signals transmitted inone or more directions by a base station 105, a UE 115 may employsimilar techniques for transmitting signals multiple times in differentdirections (e.g., for identifying a beam direction for subsequenttransmission or reception by the UE 115) or for transmitting a signal ina single direction (e.g., for transmitting data to a receiving device).

A receiving device (e.g., a UE 115) may try multiple receiveconfigurations (e.g., directional listening) when receiving varioussignals from the base station 105, such as synchronization signals,reference signals, beam selection signals, or other control signals. Forexample, a receiving device may try multiple receive directions byreceiving via different antenna subarrays, by processing receivedsignals according to different antenna subarrays, by receiving accordingto different receive beamforming weight sets (e.g., differentdirectional listening weight sets) applied to signals received atmultiple antenna elements of an antenna array, or by processing receivedsignals according to different receive beamforming weight sets appliedto signals received at multiple antenna elements of an antenna array,any of which may be referred to as “listening” according to differentreceive configurations or receive directions. In some examples, areceiving device may use a single receive configuration to receive alonga single beam direction (e.g., when receiving a data signal). The singlereceive configuration may be aligned in a beam direction determinedbased on listening according to different receive configurationdirections (e.g., a beam direction determined to have a highest signalstrength, highest signal-to-noise ratio (SNR), or otherwise acceptablesignal quality based on listening according to multiple beamdirections).

The UEs 115 and the base stations 105 may support retransmissions ofdata to increase the likelihood that data is received successfully.Hybrid automatic repeat request (HARQ) feedback is one technique forincreasing the likelihood that data is received correctly over acommunication link 125. HARQ may include a combination of errordetection (e.g., using CRC), forward error correction (FEC), andretransmission (e.g., automatic repeat request (ARQ)). HARQ may improvethroughput at the medium access control (MAC) layer in poor radioconditions (e.g., low signal-to-noise conditions). In some examples, adevice may support same-slot HARQ feedback, where the device may provideHARQ feedback in a specific slot for data received in a previous symbolin the slot. In other cases, the device may provide HARQ feedback in asubsequent slot, or according to some other time interval.

In some implementations of the present disclosure, a first device, suchas a base station 105, may transmit a signal including a number of errordetection values (e.g., error detection bits, such as parity bits)interleaved with a number of information values (e.g., information bits,such as payload bits), where the signal is encoded with a polar code. Insome cases, the base station 105 may interleave and encode the errordetection bits and the information bits with a polar code as part of anencoding process such that each error detection bit corresponds to asubset of the number of information bits. For example, each errordetection bit included in the signal may be used by a second device,such as a UE 115, to perform an error check (e.g., a parity check)associated with a subset of information bits which, if successful, mayindicate to the receiving device that the subset of information bitswere received successfully.

The UE 115 may receive the signal including the number of errordetection bits interleaved with the number of information bits in acommunication channel and the UE 115 may decode and deinterleave thesignal (e.g., as part of a decoding operation of the signal). In someexamples, the decoding operation of the signal may include decoding(e.g., successive cancelation decoding, such as with a polar code) thesignal and deinterleaving a first set of information bits in the signalfrom an error detection bit and progressively calculating an expectederror detection bit associated with the first set of information bits.In some cases, progressively calculating an expected error detection bitmay reduce latency compared to some error detection techniques that maybe implemented after the entire signal is received (e.g., whenimplemented with polar encoded signals). For example, linear-feedbackshift register (LFSR) based techniques may be implemented with polarencoded signals and may be implemented to calculate one or more expectederror detection bits after the entire signal is received. For instance,LFSR-based techniques, and other similar techniques, may calculate anexpected error detection bit after decoding and deinterleaving theentire signal and, accordingly, such techniques may preventearly-termination of the decoding process if an error is detected (e.g.,because the entire signal has already been decoded prior to detectingthe error). Techniques are provided, at least in some aspects, to enablecontinuous error detection procedures on signals that have been encodedwith polar codes and, likewise, that may be decoded with polar decoding(e.g., or any method of successive cancelation decoding).

In some implementations, the UE 115 may store one or more coefficientsused for the error detection procedure. When decoding the signal, the UE115 may use the stored coefficients to perform the error detectionprocedures and implement early-termination procedures. The UE 115 mayidentify a set of coefficients associated with the set of informationbits as part of calculating the expected error detection bit. In somecases, the set of coefficients may be based on the index valuesassociated with the first set of information bits. The UE 115 may usethe set of coefficients to calculate the expected error detection bit.In some examples, the UE 115 may compare the calculated expected errordetection bit to an error detection bit received in the signal.

In some examples, the UE 115 may determine that the second errordetection bit received in the signal is different than the expectederror detection bit. In such examples, the UE 115 may determine that thefirst set of information bits were received erroneously (e.g., thatthere is an error in one or more of the first set of information bits).Based on determining the first set of information bits were receivedincorrectly, the UE 115 may determine that the entire signal may becorrupted by the error in the first set of information bits.Accordingly, the UE 115 may terminate the decoding operation of thesignal. In some examples, this may enable the UE 115 to perform an earlytermination of the decoding operation, which may result in fewerdecoding cycles at the UE 115 and, likewise, faster processing timelinesand lower power consumption compared to a device that decodes the entiresignal prior to determining that the signal was received incorrectly.

FIG. 2 illustrates an example of a wireless communications system 200that supports error detection for a wireless channel in accordance withaspects of the present disclosure, in particular of any of the previousand following examples. In some examples, wireless communications system200 may implement aspects of wireless communications system 100.Wireless communications system 200 may include a base station 105-a anda UE 115-a, which may be examples of the corresponding devices describedwith reference to FIG. 1. The base station 105-a and the UE 115-a maycommunicate using a communication channel 205, which may be a downlinkcontrol channel, a broadcast channel, or any other suitable wirelesschannels that support communications between a base station 105-a and aUE 115-a. In some examples, the base station 105-a may transmit a signal210 to the UE 115-a and the UE 115-a may progressively perform errorchecks associated with the information or the payload included in thesignal 210. In some aspects, the data information or payload of thesignal 210 may include sets of information values, such as sets ofinformation bits 215. The UE 115-a may progressively perform the errorchecks associated with the information bits 215 included in the signal210 and, in some specific examples, may terminate decoding the signal210 (e.g., may terminate a decoding operation associated with decodingthe signal 210) prior to decoding the entire signal 210 based ondetecting an error in the signal 210.

The base station 105-a may transmit a signal 210 to the UE 115-aincluding a number of information bits 215 (e.g., the information valuesassociated with the data information or payload of the signal 210). Insome cases (e.g., if the number or size of the information bits 215 inthe signal 210 is greater than a threshold number, such as 12 bits), thebase station 105-a may determine to enable an error detectioncomputation. Based on enabling the error detection computation, the basestation 105-a may include error detection information in the signal 210that the UE 115-a may use to determine whether the signal 210 isreceived correctly. In some aspects, the error detection information mayinclude a number of error detection values, such as a number of errordetection bits 220. Accordingly, the UE 115-a may use the number oferror detection values (e.g., the number of error detection bits 220) toperform error detection computations and determine whether the signal210 is received correctly. In some cases, an error detection bit 220 maybe a CRC parity bit or a CRC bit and, likewise, the error detectioncomputation may be a CRC parity bit computation, a CRC error check, andthe like. Each error detection bit 220 of the number of error detectionbits 220 included in the signal 210 may be associated with a number ofinformation bits 215. For example, a first error detection bit 220-a maybe associated with a first set of information bits 215-a such that areceiving device, such as the UE 115-a, may use the first errordetection bit 220-a to determine if an error has occurred in one or moreof the first set of information bits 215-a. Similarly, a second errordetection bit 220 may be associated with a second set of informationbits 215, and so on throughout the signal 210.

In some cases, the base station 105-a may apply one or more identifiermasks (e.g., one or more radio network temporary identifier (RNTI)scrambling masks) to the number of error detection bits 220. Theresultant bits may be attached to the number of information bits 215included in the signal 210 and the base station 105-a may interleave thenumber of error detection bits 220 with the number of information bits215. As such, the number of error detection bits 220 may be distributedamongst the number of information bits 215. In some cases, the number oferror detection bits 220 may be distributed among sets of interleavedinformation bits 215. For example, the number of information bits 215may be transmitted in an interleaved order and sets of interleavedinformation bits 215 may be separated by an error detection bit 220. Insome cases, a first set of information bits 215-a may be associated withan error detection bit 220-a and the base station 105-a may transmit theerror detection bit 220-a after the first set of information bits 215-a.For instance, an interleaver at the base station 105-a may group bitssuch that a set of information bits 215 is received prior to an errordetection bit 220 corresponding to the set of information bits. The basestation 105-a may encode the interleaved signal 210. In some cases, thebase station 105-a may polar encode the signal 210 based on a polarencoding operation or a polar encoder. The base station 105-a maytransmit the interleaved and encoded signal 210 in communication channel205 to the UE 115-a.

The UE 115-a may receive the signal 210 and begin a decoding operationassociated with receiving the signal 210. In some cases, a polar decoderat the UE 115-a may identify a number of log-likelihood ratios (LLRs)and may generate a number of hard decision (HD) bits. In some cases, theUE 115-a may de-interleave the HD bits to separate the sets ofinformation bits 215 from the error detection bits 220. The UE 115-a mayperform an error detection computation based on the sets of informationbits 215 and the error detection bits 220. In some cases, the UE 115-amay process the information bits 215 to calculate a number of expectederror detection bits. For example, the UE 115-a may process theinformation bits 215 based on an order of reception (e.g., sequentially)employing a LFSR structure to calculate the expected error detectionbits based on the information bits 215. Based on the processing, the UE115-a may calculate a number of bits associated with the receivedinformation bits 215 and may apply an identifier mask (e.g., an RNTIscrambling mask) to the calculated bits. The result may be associatedwith one or more expected error detection bits and the UE 115-a maycompare the one or more expected error detection bits to one or moreerror detection bits 220 received in the signal 210 to detect if thereis an error in the signal 210.

For example, if the result calculated by the UE 115-a does not match oneor more of the received error detection bits 220, the UE 115-a maydetermine that an error has occurred in either the reception or thetransmission of the signal 210 or that the signal 210 is not meant forthe UE 115-a. In some cases, a difference may indicate that there is anerror in one or more of the information bits 215 received in the signal210. Additionally or alternatively, a difference between the expectederror detection bits 220 and the received error detection bits 220 maybe realized when the UE 115-a uses a different identifier mask than theidentifier mask used by the base station 105-a. In some cases, the UE115-a may attempt to blind decode the communication channel 205 (e.g.,if the communication channel 205 is a downlink control channel) byapplying different identifier masks from a set of identifier masksstored at the UE 115-a to the calculated one or more error detectionbits 220. In cases when none of the identifier masks with which the UE115-a is configured results in a successful error detection computation(e.g., a successful error check), the UE 115-a may determine that thesignal 210 was either received incorrectly or that the signal 210 wasmeant for a different UE 115 other than UE 115-a.

The LFSR-based error detection may be performed on the decoded (e.g.,polar decoded) information bits 215 upon completion of a decodingoperation of the signal 210. Accordingly, this may result in somelatency at the UE 115-a because all of the information bits 215 aredecoded, collected, and de-interleaved prior to performing errordetection. In some cases, the processing power of a hardware structureperforming LFSR-based error detection may inadequately shorten theprocessing timeline of LFSR-based error detection methods (e.g., thefinal error detection computation using an LFSR-based method may take upto 1 microsecond for each carrier of the signal 210). Additionally, whenusing an LFSR-based error detection method implemented with polardecoding, the UE 115-a may be unable to terminate a decoding operationof the signal 210 prior to completing the decoding operation because theentire signal 210 is decoded prior to performing the LFSR-based errordetection computation.

In some implementations of the present disclosure, the UE 115-a mayprogressively perform error detection computations (e.g., as the signal210 is decoded and deinterleaved). As described herein, a number oferror detection bits 220 may be interleaved with a number of informationbits 215. In some cases, each error detection bit 220 of the number oferror detection bits 220 included in the signal 210 may be associatedwith a set of information bits 215. For example, the UE 115-a may useeach error detection bit 220 to determine whether an associated set ofinformation bits 215 are received correctly. The base station 105-a mayinterleave each information bit 215 of a set of information bits 215associated with an error detection bit 220 in a way that may place atleast some information bits 215 of the set of information bits 215 infront of (e.g., prior to) the error detection bit 220 associated withthe set of information bits 215. In other words, the UE 115-a mayreceive (e.g., decode and de-interleave) a first set of information bits215-a corresponding to the first error detection bit 220-a prior toreceiving the first error detection bit 220-a. Aspects of the describedtechniques may be implemented to take advantage of such interleaving andmay enable the UE 115-a to compare a received error detection bit 220 toan expected error detection bit 220 without waiting to receive anyinformation bits 215 associated with the error detection bit 220 afterthe error detection bit 220 is received. Accordingly, the UE 115-a maybegin an error check once the error detection bit 220 is received.

In some implementations, the UE 115-a may support lower latency decodingoperations or early termination of a decoding operation based onperforming error detection computations concurrently with decoding thesignal 210 (e.g., on-the-fly), when the signal 210 was encoded using apolar code. In some examples, the UE 115-a may identify or determine anindex value of each information bit 215 of the first set of informationbits 215-a and may identify a coefficient associated with the indexvalue of each information bit 215. The UE 115-a may store thecoefficients in a memory and may retrieve the coefficients based on theidentified index value. In some cases, the coefficients associated witha set of information bits 215 may be defined by the coefficients of theoperation of Equation 1 below.

$\begin{matrix}{{r(x)} = {{{a(x)}x^{n}{mod}\;{g(x)}} = {{\left( {a_{0} + {a_{1}x} + \ldots + {a_{m - 1}x^{m - 1}}} \right)x^{n}{mod}\;{g(x)}} = {\sum\limits_{i = 0}^{m - 1}{a_{i}x^{n + 1}{mod}\;{g(x)}}}}}} & (1)\end{matrix}$

In some cases, r(x) may be a remainder, g(x) may be a polynomial (e.g.,a CRC generator polynomial), n may be the order of the polynomial, m maybe the number of information bits 215, a_(i) may be the value of aninformation bit 215 (e.g., 0 or 1), i may be the index value of theinformation bits 215, and mod may be a modulo operator.

In some cases, the coefficients may reduce to Equation 2 below.coefficients=x ^(n+i) mod g(x);i=0,1, . . . ,m−1  (2)

In some examples, the UE 115-a may use a set of coefficients associatedwith the first set of information bits 215-a to calculate an expectederror detection bit 220. For example, the UE 115-a may receive the firstset of information bits 215-a and may compute an expected errordetection bit 220 based on the coefficients associated with the firstset of information bits 215-a (e.g., associated with the index values ofthe first set of information bits 215-a). In some examples, the UE 115-amay compute the expected error detection bit 220 based on thecoefficients associated with the first set of information bits 215-a andan identifier mask stored at the UE 115-a. The UE 115-a may receive anerror detection bit 220-a in the signal 210 associated with the firstset of information bits 215-a and may compare the received errordetection bit 220-a with the calculated error detection bit 220 as partof an error check.

In some implementations, the UE 115-a may determine that the receivederror detection bit 220-a and the calculated error detection bit 220 aredifferent. Accordingly, the UE 115-a may determine that one or more ofthe first set of information bits 215-a were received incorrectly andmay terminate the decoding operation of the signal 210 before completingthe decoding operation (e.g., decoding and de-interleaving the entiresignal 210). As such, the UE 115-a may perform fewer decoding cycles andspend a longer time in a sleep mode (e.g., a micro-sleep mode), whichmay result in reduced power consumption at the UE 115-a.

FIG. 3 illustrates an example of a process flow 300 that supports errordetection for a wireless channel in accordance with aspects of thepresent disclosure, in particular of any of the previous and followingexamples. In some examples, process flow 300 may implement aspects ofwireless communications systems 100 or 200. Process flow 300 may includea number of operations performed by a device in accordance with thetechniques described herein. In some examples, process flow 300 mayillustrate an example of hardware (e.g., including circuitry, processingblocks, logic components, and other components) that may perform theoperations of process flow 300. For example, process flow 300 mayinclude procedures performed by a device, such as a UE 115, thatreceives a signal from another device, such as a base station 105.

At 305, the device may receive a signal. In some examples, the signalmay include error detection information, which may include a number oferror detection values or a number of error detection bits. with thesignal may also include data information or a payload, which may includea number of information values or a number of information bits. In someaspects, the number of error detection values (e.g., the number of errordetection bits) may be interleaved with the number of information values(e.g., the number of information bits). Additionally or alternatively,the signal may be encoded (e.g., polar encoded). In some examples,receiving the signal may include performing a decoding operation of thesignal, which may include a decoding procedure and a deinterleavingprocedure. For instance, receiving the signal at 305 may further includedecoding the signal at 310 and deinterleaving the signal at 315. In somecases, the device may receive (e.g., decode and deinterleave) a singlebit at a time. In some other cases, the device may receive a number ofbits (e.g., a batch of bits) together.

At 310 the device may decode (e.g., polar decode) the signal. In someimplementations, the device may progressively decode the signal usingthe polar code to identify an information bit (or a batch of informationbits) of the number of information bits or an error detection bit of thenumber of error detection bits.

In some cases, the device may perform decoding based on a successivecancellation decoding procedure and the number of bits in the signal maybe decoded progressively. For example, in polar decoding, a first bit(or a first batch of bits) may be decoded, then a second bit (or asecond batch of bits) may be decoded based on completing the polardecoding of the first bit (or the first batch of bits), and so on untilthe signal is completely decoded or the decoding operation of the signalis terminated.

At 315, the device may deinterleave the signal. In some implementations,the device may deinterleave an error detection bit from the number ofinformation bits included in the signal. In some implementations, basedon deinterleaving the signal, the device may reorder the number ofinformation bits in the signal such that sets of information bits thatare associated with the same error detection bit may be grouped together(e.g., in a successive or consecutive order). For example, a first setof information bits associated with a first error detection bit may begrouped together and a second set of information bits associated with asecond error detection bit may be grouped together and may follow thefirst set of information bits. In some examples, the UE 115 may receive(e.g., decode and de-interleave) the signal and may progressively useinformation bits to calculate an expected error detection bit as part ofan error detection method.

At 320, the device may identify a coefficient associated with aninformation bit. In some examples, the device may identify a coefficientbased on an index value associated with a first information bit. Theindex value may be associated with an original index value of theinformation bit, an interleaved index value, or a deinterleaved indexvalue.

At 325, the device may identify a coefficient for the first informationbit. In some cases, the coefficient is identified based on an indexvalue for the first information bit. In some cases, a coefficientassociated with an information bit may be determined based on Equation2. In some implementations, the device may pre-calculate thecoefficients according to Equation 2 and store the coefficients in amemory of the device (e.g., in a look up table (LUT) at the device). Insome examples, the LUT may have m rows and n columns, where m is thenumber of information bits in the signal and n is the order of the CRCgenerator polynomial. In some cases, a signal may include up to 140information bits and the CRC generator polynomial may have an order upto 24. As such, a single 140×24 LUT may be sufficiently large to storethe coefficients for a quantity of possible signals. The device mayidentify or determine an index value for an information bit and identifya corresponding location in the LUT based on the identified index valuethat includes the coefficient associated with the information bit.

At 330, the device may store the coefficient identified in the memory(e.g., the coefficient associated with the information bit) in anaccumulator. In some specific implementations, the device mayprogressively identify a coefficient for each information bit of a firstset of information bits as the first set of information bits arereceived and store each coefficient in the accumulator (e.g., theaccumulator may include a continuous sum of the identifiedcoefficients).

At 335, the device may calculate a first error detection bit based onthe accumulated coefficients and the first set of information bits. Insome examples, the first error detection bit may be progressivelycomputed based on progressively accumulating the coefficients in theaccumulator. For example, the device may continuously calculate thefirst error detection bit based on the most recently received (e.g.,decoded and deinterleaved) information bit. As such, approximately assoon as an error detection bit is received the device may determinewhether the signal has been received correctly (e.g., the continuouslycalculated first error detection bit will be equal to the received errordetection bit at approximately the time when the error detection bit isreceived).

At 340, the device may apply one or more identifier masks to thecalculated first error detection bit. The device may use the identifiermask as part of a blind decoding procedure (e.g., when the signal istransmitted in a downlink control channel) so that the device maydetermine if the signal was meant for the device. For instance, thesignal may be associated with a first identifier mask (e.g., based on atransmitting device applying the first identifier mask). The device mayapply one or more identifier masks that are known to the device (e.g.,configured on the device) and the device may perform the blind decodingprocedure successfully if the device is configured with and applies thefirst identifier mask. In some cases, the identifier mask may be ascrambling mask, such as an RNTI scrambling mask. Additionally oralternatively, the device may be configured with one or more identifiermasks by higher layer signaling.

At 345, the device may compare the calculated first error detection bitto the received error detection bit associated with the first set ofinformation bits in the signal. In some implementations, the device maydetermine that the calculated first error detection bit and that thereceived error detection bit are different. Accordingly, at 350, thedevice may determine that one or more of the first set of informationbits may be incorrectly received. In such examples, the device mayterminate the decoding operation of the signal at 355.

In some other implementations, the device may determine that thecalculated first error detection bit is the same as the received errordetection bit. Accordingly, at 350, the device may determine that theerror check passed and that the one or more information bits of thefirst set of information bits. Based on passing the error check at 350,the device may continue to progressively receive (e.g., decode andde-interleave) the signal at 305.

FIG. 4 illustrates an example of a process flow 400 that supports errordetection for a wireless channel in accordance with aspects of thepresent disclosure, in particular of any of the previous or followingexamples. In some examples, process flow 400 may implement aspects ofwireless communications systems 100 or 200. The process flow 400 mayillustrate operations at a device, such as a UE 115 as described withreference to FIG. 1.

In some examples, a smaller, reduced-size, or down-sampled LUT may beused to output coefficients associated with a subset of the index valuesof the information bits (e.g., the information values) in the signal(e.g., a subset of index values of the total number of index values,such as indicated by a specification). In some specific examples, theLUT may be a down-sampled version of the LUT as described with referenceto FIG. 3. As such, the down-sampled LUT may include fewer table entriesand use less memory of the device. For instance, an application-specificintegrated circuit (ASIC) may be employed to perform one or more aspectsof the present disclosure and, in some cases, reducing the size of theLUT may reduce the amount of area that the ASIC may use or a memoryassociated with the ASIC or LUT may use to store the LUT. Accordingly,in some cases, the ASIC may use less material to construct the memory(e.g., silicon).

Reducing the size of the memory, however, may result in one or morevalues being missing from the memory (e.g., missing from the LUT). Forexample, one or more entries in the LUT (e.g., corresponding to indexvalues of one or more information bits or values) may not have a storedcoefficient (e.g., the device may not store a pre-calculated coefficientfor a subset of index values when using a reduced-size LUT).Accordingly, when the device decodes and deinterleaves an informationbit with an index value corresponding to an empty entry in the LUT, thedevice may compute any missing coefficient concurrently with thedecoding operation of the signal (e.g., on-the-fly) using one or morealgorithms to interpolate the value of the coefficient.

In some examples, when using the reduced-size memory, the coefficientsmay be computed or determined based on Equation 3 below.

$\begin{matrix}{{r(x)} = {{\sum\limits_{i = 0}^{m - 1}{a_{i}x^{n + i}{mod}\;{g(x)}}} = {{\sum\limits_{i = 0}^{\frac{m}{2^{k}} - 1}{\sum\limits_{j = 0}^{2^{k} - 1}{{a_{({{2^{k} \times i} + j})}\left( x^{n + {({{2^{k} \times i} + j})}} \right)}{mod}\;{g(x)}}}} = {{\sum\limits_{i = 0}^{\frac{m}{2^{k}} - 1}{\sum\limits_{j = 0}^{2^{k} - 1}{{a_{({{2^{k} \times i} + j})}\left( {x^{j}x^{n + {({2^{k} \times i})}}} \right)}{mod}\;{g(x)}}}} = {\sum\limits_{i = 0}^{\frac{m}{2^{k}} - 1}{\sum\limits_{j = 0}^{2^{k} - 1}{{a_{({{2^{k} \times i} + j})}\left( {x^{j} \cdot \left( {x^{n + {({2^{k} \times i})}}{mod}\;{g(x)}} \right)} \right)}{mod}\;{g(x)}}}}}}}} & (3)\end{matrix}$

In some cases, 2^(k) is a down-sampling factor and k may be apredetermined or preconfigured value. In some cases, i may be an integerfrom 0 to

$\frac{m}{2^{k}} - 1$and j may be an integer from 0 to 2^(k)−1. Process flow 400 mayillustrate an example method for how the device may receive a signal andidentify which index values of information bits have coefficients (e.g.,pre-calculated coefficients) included in the memory and which indexvalues of information bits the device may compute coefficients for. Insome examples, process flow 400 may additionally illustrate an exampleof hardware (e.g., including circuitry, processing blocks, logiccomponents, and other components) that may perform the operations ofprocess flow 400.

At 405, the device may receive a signal (e.g., from a transmittingdevice, such as a base station 105) over a communication channel (e.g.,a downlink control channel). In some cases, the signal may include errordetection information, which may include a number of error detectionvalues, such as a number of error detection bits. The signal may alsoinclude data information or a payload, which may include a number ofinformation values, such as a number of information bits. In someaspects, the number of error detection values (e.g., the number of errordetection bits) may be interleaved with the number of information values(e.g., the number of information bits) and the signal may be encoded(e.g., polar encoded). In some examples, receiving the signal mayinclude performing a decoding operation of the signal, which may includea decoding procedure and a de-interleaving procedure. For instance,receiving the signal at 405 may further include decoding the signal at410 and de-interleaving the signal at 415. In some cases, the device mayreceive (e.g., decode and deinterleave) a single bit (e.g., a singlevalue) at a time. In some other cases, the device may receive a numberof bits or a number of values (e.g., a batch of bits or a batch ofvalues) together.

At 410, the device may decode (e.g., polar decode) the signal. In somecases, the decoding at 410 may be similar to the decoding at 310, asdescribed with reference to FIG. 3. For example, in someimplementations, the device may progressively decode the signal usingthe polar code to identify an information bit (or a batch of informationbits) of the number information bits in the signal or an error detectionbit of the number of error detection bits in the signal.

At 415, the device may deinterleave the signal. In some cases, thedecoding at 415 may be similar to the decoding at 315, as described withreference to FIG. 3. For example, in some implementations, the devicemay identify an error detection bit at 410 and may deinterleave theerror detection bit from the number of information bits. Additionally oralternatively, the device may deinterleave one or more information bits.

At 420, the device may identify a coefficient associated with aninformation bit of the signal. In some examples, the device may use thecoefficient to calculate an error detection bit associated with theinformation bit. The device may progressively identify a coefficient foreach information bit of the signal as the signal is decoded. Forexample, the device may decode a first information bit at 410 and mayidentify the coefficient associated with the first information bit at420.

In some implementations, the device may identify a coefficientassociated with an information bit using the reduced-size memory.Accordingly, the device may identify a coefficient associated with aninformation bit from the memory (e.g., when a first index value of theinformation bit corresponds to a pre-calculated coefficient in thememory) or may calculate the coefficient (e.g., when the first indexvalue of the information bit corresponds to a missing value in thememory).

At 425, the device may determine whether the information bit (e.g., thefirst index value of the information bit) corresponds to apre-calculated coefficient stored in a memory (e.g., in the LUT). Insome examples, the device may identify that the information bit belongsto a first group of information bits associated with pre-calculatedcoefficients stored in the memory. In some other examples, the devicemay identify that the information bit belongs to a second group ofinformation bits without pre-calculated coefficients stores in thememory (e.g., associated with empty or missing entries in the LUT in thememory). In some implementations, the device may identify that theinformation bit belongs to the first group of information bits or thesecond group of information bits based on the size of the memory. Forexample, the device may determine whether the memory is a reduced-sizememory or includes a down-sampled LUT, or both. In some specificexamples, the device may determine that the information bit belongs tothe first group of information bits or the second group of informationbits based on a down-sampling factor associated with the reduced-sizememory or down-sampled LUT.

At 425-a, the device may determine that the information bit belongs tothe first group of information bits. In some examples, the device maydetermine that the information bit belongs to the first group ofinformation bits if the down-sampling factor divides evenly into thefirst index value (e.g., when a remainder of the division is zero). Insome implementations, the device may identify a second index valueassociated with the information bit based on the first index value ofthe information bit to determine that the information bit belongs to thefirst group of information bits. For example, in some specificimplementations, the entries of the reduced-size memory (e.g., includinga down-sampled LUT) may be different than the entries of the completememory (e.g., including a complete LUT, such as a 140×24 LUT). Forinstance, the reduced-size memory may include the number of entries ofthe complete memory divided by the down-sampling factor (e.g., 2^(k)) Insome cases, the size of the memory may be reduced to include entriesthat include coefficients, where entries that would not include acoefficient (e.g., after down-sampling) are removed from the memory. Insuch cases, the first index value of the information bit may correspondto a different coefficient (e.g., an incorrect coefficient) in thereduced-size memory than in the full-size memory or may not correspondto an entry (e.g., when the first index of the information bit isgreater than the size of the down-sampled LUT included in thereduced-size memory).

Accordingly, the device may identify or determine a second index valuebased on the first index value, the down-sampling factor, and anoperation (e.g., a mathematical operation) that may correspond to thecorrect entry (e.g., the correct coefficient) in the reduced-sizememory. In some examples, the device may identify or determine thesecond index value based on dividing the first index value by thedown-sampling factor (e.g., 2^(k)). At 430, the device may use thesecond index value to identify a coefficient (e.g., a pre-calculatedcoefficient) in the memory. In some examples, the coefficients includedin the memory may be pre-calculated based on Equation 4 below.

$\begin{matrix}{{{{coefficients} = {x^{n + {({2^{k} \times i})}}{mod}\;{g(x)}}};{i = 0}},1,\ldots\mspace{14mu},{\frac{m}{2^{k}} - 1}} & (4)\end{matrix}$

At 425-b, the device may determine that the information bit belongs tothe second group of information bits. In some cases, the device maydetermine that the information bit belongs to the second group ofinformation bits if there is a remainder after dividing the first indexvalue by the down-sampling factor. Accordingly, the device may determinethat the reduced-size memory may not include a coefficient (e.g., apre-calculated coefficient) associated with the information bit and thedevice may calculate the coefficient instead. In some aspects, thecoefficients associated with the second group of information bits may bedetermined based on an operation (e.g., a modulo operation) applied tothe first index value of the information bit and the down-samplingfactor. For example, the remainder after dividing the first index valueof the information bit by the down-sampling factor (e.g., 2^(k)) maycorrespond to a proximity value between the first index value of theinformation bit and one or more index values (e.g., a second indexvalue) of one or more information bits included in the reduced-sizememory.

In some examples, the remainder (e.g., the proximity value) may be athird index value. In some aspects, the third index value may be adifference between the first index value of the information bit and oneor more next-closest index values (e.g., a second index value) thatcorrespond to one or more information bits included in the reduced-sizememory. In some implementations, the device may calculate thecoefficient associated with the information bit based on thepre-calculated coefficients associated with the nearest one or moreinformation bits at 435.

At 435, the device may identify (e.g., calculate) the coefficientassociated with the information bit. In some aspects, the operations at435 may be performed by a CRC generation block. In some specificimplementations, the CRC generation block may take inputs of the CRCgenerator polynomial and the one or more coefficients of the nearest oneor more information bits that are included in the memory. In someexamples, the coefficient of the information bit may be calculatedaccording to Equation 5 below.(x·x ^(n+(2) ^(k) ^(×i)))mod g(x)(x ² ·x ^(n+(2) ^(k) ^(×i)))mod g(x)=x·(x·x ^(n+(2) ^(k) ^(×i))modg(x))mod g(x)  (5)

Additionally, the device may use similarly expanded or higher orderequations related to Equation 5 to calculate the coefficients forinformation bits included in the second group of information bits (e.g.,associated with missing coefficients in the reduced-size memory). Insome cases, Equation 5 may be executed by circuit (e.g., a digitalcircuit) employing a simplified Galois multiplier. In such cases, thesimplified Galois multiplier may compute functions associated with amathematical form of (x·v(x)) mod g(x), as described in further detailin FIGS. 5 and 6. In some cases, the Galois multiplier may refer to afinite field with a finite number of elements that is used as part offinite field arithmetic.

At 440, the device may add the identified coefficient (e.g., eithercalculated or identified in the memory) associated with the informationbit to an accumulator. In some cases, the accumulator may store acontinuous sum of coefficients associated with information bits. Assuch, the accumulator may store a running (e.g., continuous,progressive, etc.) total of the coefficients associated with a number ofreceived information bits. In some implementations, the running total ofthe coefficients may be used for error detection bit computation (e.g.,at 445).

In some specific implementations, the device may accumulate a firstnumber of coefficients prior to receiving (e.g., decoding andde-interleaving) an error detection bit. The device may use theaccumulated first number of coefficients, at 445, to calculate an errordetection bit (e.g., an expected error detection bit) associated withthe first set of information bits. In some cases, the device may clearthe accumulator upon the calculation at 445 in order to beginaccumulating a second number of coefficients associated with a secondset of information bits, the second set of information bits associatedwith a second error detection bit (e.g., different than the first errordetection bit). In some other cases, the device may employ a number ofaccumulators and may accumulate the first number of coefficients in afirst accumulator and the second number of coefficients in a secondaccumulator. In such cases, the device may support progressive errorchecks even when the first set of information bits associated with thefirst error detection bit and the second set of information bitsassociated with the second error detection bit overlap (e.g., when eachset of information bits associated with a different error detection bitare not transmitted consecutively in the signal).

At 450, the device may apply one or more identifier masks to thecomputed error detection bit. The device may use the identifier mask aspart of a blind decoding procedure (e.g., when the signal is transmittedin a downlink control channel) so that the device may determine if thesignal was meant for the device. For instance, the signal may beassociated with a first identifier mask (e.g., based on the transmittingdevice applying the first identifier mask). The device may apply one ormore identifier masks that are known to the device (e.g., configured onthe device) and the device may perform the blind decoding proceduresuccessfully if the device is configured with and applies the firstidentifier mask. In some cases, the identifier mask may be a scramblingmask, such as an RNTI scrambling mask. Additionally or alternatively,the device may be configured with one or more identifier masks by higherlayer signaling.

At 455, the device may compare the calculated error detection bit to anerror detection bit that was received in the signal, where thecalculated error detection bit was calculated based on a set ofinformation bits associated with the received error detection bit. At460, the device may determine whether the error check passes or fails.For instance, if the calculated error detection bit and the receivederror detection bit are the same, the device may determine that theerror check passes and may continue receiving (e.g., decoding andde-interleaving) the signal. If the calculated error detection bit andthe received error detection bit are different, the device may determinethat the error check fails. Accordingly, at 465, the device mayterminate the decoding operation (e.g., decoding and de-interleaving) ofthe signal.

In some implementations, the device may terminate the decoding operationof the signal before the decoding operation of the signal is complete(e.g., prior to decoding and de-interleaving the entire signal). Thismay allow the device to perform an early termination of the decodingoperation based on progressively comparing a received error detectionbit with a calculated error detection bit concurrently with receivingthe signal. In some cases, as described herein, the error detection bitsmay be CRC parity bits. As such, an early termination based on thedescribed techniques may be a CRC-based early termination.

FIG. 5 illustrates an example of a circuit 500 that supports errordetection for a wireless channel in accordance with aspects of thepresent disclosure, in particular of any of the previous and followingexamples. In some examples, the circuit 500 may implement aspects ofwireless communications systems 100 or 200. The circuit 500 may includehardware capable of performing the operations of the techniquesdescribed herein. The circuit 500 may include a CRC generator block 505.In some examples, the CRC generator block 505 may be implemented tocalculate an error detection bit associated with a set of informationbits, as described in more detail in FIG. 4.

The CRC generator block 505 may include a quantity i of circuits 510,including circuit 510-a, circuit 510-b, and circuit 510-c, and amultiplexer 515. In some examples, the CRC generator block 505 maycalculate error detection information, such as an error detection valueor an error detection bit associated with data information or a payloadincluded in the signal, such as a first information value or a firstinformation bit. In some aspects, the first information value (e.g., thefirst information bit) may be associated with an index value that maynot be included in a reduced-size memory (e.g., including a down-sampledLUT). In some implementations, the CRC generator block 505 may receivean input 520 including one or more coefficients associated with one ormore information values (e.g., one or more information bits) that areproximate to the first information value (e.g., the first informationbit). In some specific implementations, the input 520 may be a functionassociated with coefficients associated with information values orinformation bits included in the reduced-size memory. For instance, afunction v(x) associated with the outputs (e.g., coefficients for errordetection bit computation) of the reduced-size memory may be provided tothe CRC generator block 505 and the CRC generator block 505 maycalculate a coefficient associated with the first information bit basedon the function v(x) and the result of a modulo operation applied to theindex value of the first information bit and the down-sampling factor(e.g., where the result may include a proximity to one or more indexvalues of information bits included in the reduced-size memory), asdescribed in more detail in FIG. 4. In some aspects, the function v(x)may be defined by Equation 6 below.v(x)=x ^(n+(2) ^(k) ^(×i))mod g(x)  (6)In some cases, Equation 6 may be similar to (e.g., or the same as)Equation 4 when

${i = 0},1,\ldots\mspace{14mu},{\frac{m}{2^{k}} - 1}$(e.g., may correspond to the coefficients that are pre-calculated andstored in the reduced-size memory when the down-sampling factor is2^(k))

In some implementations, CRC generator block may take the input 520 andcalculate a coefficient for the first information bit based on acombination of a number (e.g., i) of operations performed by circuits510. In some cases, the circuits 510 may perform similar (e.g., or thesame) operations and the number of circuits 510 used to calculate acoefficient may be based on the down sampling factor. In some specificimplementations, the number of circuits 510 may be equal to thedown-sampling factor minus an integer (e.g., 2). For instance, i may beequal to 2^(k)−2. In some aspects, the number of circuits 510-c may bechained together (e.g., may be connected in series) and each circuit510-c may provide an output to the multiplexer 515.

The multiplexer 515 may receive the outputs of each of the circuits 510and, in some cases, may also receive input 520. In some implementations,the multiplexer 515 may determine the coefficient 525 associated withthe first information bit based on receiving the outputs of the circuits510. The multiplexer 515 may multiplex the outputs of the circuits 510or otherwise interpolate the outputs to determine the coefficient 525.In some aspects, the multiplexer 515 may be associated with adown-sampling factor of a reduced-size or down-sampled memory. Forexample, in the case when the down-sampling factor is 2^(k), themultiplexer 515 may be a 2^(k) to 1 multiplexer. In some examples, theCRC generator block 505 may output the coefficient 525 to anaccumulator, as described in more detail in FIG. 4.

FIG. 6 illustrates an example of a circuit 600 that supports errordetection for a wireless channel in accordance with aspects of thepresent disclosure, in particular of any of the previous and followingexamples. In some examples, the circuit 600 may implement aspects ofwireless communications systems 100 or 200. In some examples, thecircuit 600 may be an example of a circuit 510, as described withreference to FIG. 5.

The circuit 600 may have inputs of v(x) (e.g., associated with theoutput of coefficients in the memory) and g(x) (e.g., the CRC generatorpolynomial or matrix). The circuit 600 may perform operations of asimplified Galois multiplier and may be used to compute mathematicalfunctions of the form (x·v(x)) mod g(x). In some aspects, v(x)=v₀+v₁x+ .. . +v_(n-1)x^(n−1), where the order of v(x) may be less than the orderof g(x). In some examples, the circuit 600 may be implemented to computeEquation 7, as shown below.(x·v(x))mod g(x)=(c _(n-1) g ₀)+(v _(n-1) g ₁ +v ₀)x+ . . . +(v _(n-1) g_(n-1) +v _(n-2))x ^(n−1)  (7)

In some aspects, the circuit 600 may be implemented to perform a basic(e.g., simplified) mathematical operation and a number of circuits 600may be chained together (e.g., within a CRC generator block, asdescribed with reference to FIG. 5) to perform higher order or morecomplex operations. As described in more detail in FIG. 5, a number ofcircuits 600 (e.g., a number equal to the down-sampling factor minus 2)may be chained together to determine a coefficient associated with afirst information value (e.g., a first information bit) based on thecoefficients associated with one or more information values (e.g., oneor more information bits) with index values proximate to the index valueof the first information value. In some cases, the circuit 600 maygenerate a number of copies (e.g., n copies) based on the order of theCRC generator polynomial g(x).

FIG. 7 shows a block diagram 700 of a device 705 that supports errordetection for a wireless channel in accordance with aspects of thepresent disclosure, in particular of any of the previous and followingexamples. The device 705 may be an example of aspects of a UE 115 asdescribed herein. The device 705 may include a receiver 710, acommunications manager 715, and a transmitter 720. The device 705 mayalso include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 710 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to errordetection method for a wireless channel, etc.). Information may bepassed on to other components of the device 705. The receiver 710 may bean example of aspects of the transceiver 1020 described with referenceto FIG. 10. The receiver 710 may utilize a single antenna or a set ofantennas.

The communications manager 715 may receive a signal that includes a setof error detection bits interleaved with a set of information bits,identify a coefficient associated with a first information bit of theset of information bits and used for calculating at least one errordetection bit based on receiving the signal, calculate the first errordetection bit based on the coefficient and the first information bit,determine that a second error detection bit received in the signal andassociated with the first information bit is different than the firsterror detection bit calculated using the coefficient and the firstinformation bit, and terminate a decoding operation of the signal beforethe decoding operation is complete based on determining that the firsterror detection bit is different than the second error detection bit.The communications manager 715 may be an example of aspects of thecommunications manager 1010 described herein.

The communications manager 715 may also receive a signal that includes aset of error detection values and a set of information values, determinea coefficient, the coefficient associated with a first information valueof the set of information values, configured for determining at leastone error detection value, determine a first error detection value basedon the coefficient associated with the first information value,determine that a second error detection value received in the signal andassociated with the first information value is different than the firsterror detection value, and terminate decoding of the signal based on thefirst error detection value and the second error detection value. Thecommunications manager 715 may be an example of aspects of thecommunications manager 1010 described herein.

The communications manager 715, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 715, or itssub-components may be executed by a general-purpose processor, a digitalsignal processor (DSP), an ASIC, a field-programmable gate array (FPGA)or other programmable logic device, discrete gate or transistor logic,discrete hardware components, or any combination thereof designed toperform the functions described in the present disclosure.

The communications manager 715, or its sub-components, may be physicallylocated at various positions, including being distributed such thatportions of functions are implemented at different physical locations byone or more physical components. In some examples, the communicationsmanager 715, or its sub-components, may be a separate and distinctcomponent in accordance with various aspects of the present disclosure.In some examples, the communications manager 715, or its sub-components,may be combined with one or more other hardware components, includingbut not limited to an input/output (I/O) component, a transceiver, anetwork server, another computing device, one or more other componentsdescribed in the present disclosure, or a combination thereof inaccordance with various aspects of the present disclosure.

The transmitter 720 may transmit signals generated by other componentsof the device 705. In some examples, the transmitter 720 may becollocated with a receiver 710 in a transceiver module. For example, thetransmitter 720 may be an example of aspects of the transceiver 1020described with reference to FIG. 10. The transmitter 720 may utilize asingle antenna or a set of antennas.

In some examples, the communications manager 715 may be implemented asan integrated circuit or chipset for a mobile device modem, and thereceiver 710 and transmitter 720 may be implemented as analog components(e.g., amplifiers, filters, antennas) coupled with the mobile devicemodem to enable wireless transmission and reception over one or morebands.

The communications manager 715 as described herein may be implemented torealize one or more potential advantages. One implementation may allowthe device 705 to more efficiently terminate a decoding operation of asignal before completing the decoding operation based on progressively(e.g., continuously) computing an expected error detection bit as thesignal is received (e.g., decoded and deinterleaved). By progressivelycomputing an expected error detection bit, the device 605 may comparethe expected error detection bit to an error detection bit received inthe signal approximately as soon as the error detection bit is receivedin the signal.

Based on techniques for more efficiently terminating a decodingoperation of a signal, the communications manager 715 may lower latencyassociated with the decoding operation and may also perform fewerdecoding cycles (e.g., when the device performs an early termination ofthe decoding operation). As such, the one or more processing blocks ofthe device 705 may enter a sleep mode (e.g., a micro sleep mode in whichthe one or more processing blocks of the device 705 may operate at a lowor zero power consumption level) for a longer duration, which may resultin an increase of power savings and a longer battery life. Additionallyor alternatively, one or more processing blocks of the device 705 may bere-tasked from the decoding operation to another processing task at thedevice 705, which may improve processing efficiency at the device 605.

FIG. 8 shows a block diagram 800 of a device 805 that supports errordetection for a wireless channel in accordance with aspects of thepresent disclosure, in particular of any of the previous and followingexamples. The device 805 may be an example of aspects of a device 705,or a UE 115 as described herein. The device 805 may include a receiver810, a communications manager 815, and a transmitter 840. The device 805may also include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 810 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to errordetection method for a wireless channel, etc.). Information may bepassed on to other components of the device 805. The receiver 810 may bean example of aspects of the transceiver 1020 described with referenceto FIG. 10. The receiver 810 may utilize a single antenna or a set ofantennas.

The communications manager 815 may be an example of aspects of thecommunications manager 715 as described herein. The communicationsmanager 815 may include a signal manager 820, a coefficient manager 825,an error detection manager 830, and a decoding manager 835. Thecommunications manager 815 may be an example of aspects of thecommunications manager 1010 described herein.

The signal manager 820 may receive a signal that includes a set of errordetection bits interleaved with a set of information bits. In someexamples, the signal manager 820 may receive a signal that includes aset of error detection values and a set of information values.

The coefficient manager 825 may identify a coefficient associated with afirst information bit of the set of information bits and used forcalculating at least one error detection bit based on receiving thesignal. In some examples, the coefficient manager 825 may determine acoefficient, the coefficient associated with a first information valueof the set of information values, configured for determining at leastone error detection value.

The error detection manager 830 may calculate the first error detectionbit based on the coefficient and the first information bit and determinethat a second error detection bit received in the signal and associatedwith the first information bit is different than the first errordetection bit calculated using the coefficient and the first informationbit. In some examples, the error detection manager 830 may determine afirst error detection value based on the coefficient associated with thefirst information value and determine that a second error detectionvalue received in the signal and associated with the first informationvalue is different than the first error detection value.

The decoding manager 835 may terminate a decoding operation of thesignal that, in some examples, may use a polar code before the decodingoperation is complete based on determining that the first errordetection bit is different than the second error detection bit. In someexamples, the decoding manager 835 may terminate decoding of the signalbased on the first error detection value and the second error detectionvalue.

The transmitter 840 may transmit signals generated by other componentsof the device 805. In some examples, the transmitter 840 may becollocated with a receiver 810 in a transceiver module. For example, thetransmitter 840 may be an example of aspects of the transceiver 1020described with reference to FIG. 10. The transmitter 840 may utilize asingle antenna or a set of antennas.

FIG. 9 shows a block diagram 900 of a communications manager 905 thatsupports error detection for a wireless channel in accordance withaspects of the present disclosure, in particular of any of the previousand following examples. The communications manager 905 may be an exampleof aspects of a communications manager 715, a communications manager815, or a communications manager 1010 described herein. Thecommunications manager 905 may include a signal manager 910, acoefficient manager 915, an error detection manager 920, a decodingmanager 925, a down-sampling manager 930, a deinterleaving manager 935,and a power mode manager 940. Each of these modules may communicate,directly or indirectly, with one another (e.g., via one or more buses).

The signal manager 910 may receive a signal that includes a set of errordetection bits interleaved with a set of information bits. In someexamples, the signal manager 910 may receive a signal that includes aset of error detection values and a set of information values.

In some examples, the signal manager 910 may identify an index value forthe first information bit based on receiving the signal, whereidentifying the coefficient is based on identifying the index value. Insome examples, identifying a set of information bits of the signalassociated with the second error detection bit based on receiving thesignal, where the set of information bits includes the first informationbit. In some cases, the signal includes a downlink control channel.

In some examples, the signal manager 910 may determine an index valueassociated with the first information value based on receiving thesignal, where determining the coefficient is based on determining theindex value. In some examples, identifying a set of information valuesof the signal associated with the second error detection value based onreceiving the signal, where the set of information values includes thefirst information value. In some cases, the set of error detectionvalues is interleaved with the set of information values.

The coefficient manager 915 may identify a coefficient associated with afirst information bit of the set of information bits and used forcalculating at least one error detection bit based on receiving thesignal. In some examples, the coefficient manager 915 may retrieve thecoefficient from a memory based on the index value identified for thefirst information bit. In some examples, the coefficient manager 915 mayretrieve a value from a memory based on the second index value, wherethe coefficient is identified based on the value retrieved from thememory and a third index value.

In some examples, the coefficient manager 915 may accumulate one or moreinformation bits and one or more coefficients, where calculating thefirst error detection bit is based on accumulating the set ofinformation bits and the one or more coefficients. In some examples, thecoefficient manager 915 may identify a set of coefficients, eachcoefficient of the set of coefficients associated with an informationbit of the set of information bits based on identifying the set ofinformation bits, where calculating the first error detection bit isbased on the set of coefficients and the set of information bits. Insome examples, the coefficient manager 915 may identify the coefficientoccurs while the signal is being decoded using a polar code.

The coefficient manager 915 may determine a coefficient, the coefficientassociated with a first information value of the set of informationvalues, configured for determining at least one error detection value.In some examples, the coefficient manager 915 may retrieve thecoefficient from a memory based on the determined index value. In someexamples, the coefficient manager 915 may retrieve a value from a memorybased on the second index value, where the coefficient is determinedbased on the value retrieved from the memory and the third index value.

In some examples, the coefficient manager 915 may accumulate one or moreinformation values and one or more coefficients, where determining thefirst error detection value is based on accumulating the set ofinformation values and the one or more coefficients. In some examples,the coefficient manager 915 may determine a set of coefficients, eachcoefficient of the set of coefficients associated with an informationvalue of the set of information values based on identifying the set ofinformation values, where determining the first error detection value isbased on the set of coefficients and the set of information values.

The error detection manager 920 may calculate the first error detectionbit based on the coefficient and the first information bit. In someexamples, the error detection manager 920 may determine that a seconderror detection bit received in the signal and associated with the firstinformation bit is different than the first error detection bitcalculated using the coefficient and the first information bit. In someexamples, the error detection manager 920 may apply an identifier maskto the first error detection bit, where determining that the first errordetection bit is different than the second error detection bit is basedon applying the identifier mask to the first error detection bit.

In some examples, the error detection manager 920 may apply a set ofidentifier masks to the first error detection bit to generate a set ofcandidate bits, respectively. In some examples, the error detectionmanager 920 may compare each bit of the set of candidate bits to thesecond error detection bit, where determining that the first errordetection bit is different than the second error detection bit is basedon comparing each bit of the set of candidate bits to the second errordetection bit. In some cases, the first error detection bit iscalculated using any numerical quantity of information bits andcoefficients. In some cases, the first error detection bit includes aCRC bit.

The error detection manager 920 may determine a first error detectionvalue based on the coefficient associated with the first informationvalue. In some examples, the error detection manager 920 may determinethat a second error detection value received in the signal andassociated with the first information value is different than the firsterror detection value. In some examples, the error detection manager 920may apply an identifier mask (e.g., an RNTI) to the first errordetection value, where determining that the first error detection valueis different than the second error detection value is based on applyingthe identifier mask to the first error detection value.

In some examples, the error detection manager 920 may apply a set ofidentifier masks (e.g., a set of RNTIs) to the first error detectionvalue to generate a set of candidate values, respectively. In someexamples, the error detection manager 920 may compare each value of theset of candidate values to the second error detection value, wheredetermining that the first error detection value is different than thesecond error detection value is based on comparing each value of the setof candidate values to the second error detection value.

In some examples, the error detection manager 920 may compare the firsterror detection value with the second error detection value, wheredetermining that the first error detection value is different than thesecond error detection value is based on comparing the first errordetection value with the second error detection value. In some cases, anerror detection value may include an error detection bit and aninformation value may include an information bit. In some cases, thefirst error detection value is determined using the coefficient and thefirst information value.

The decoding manager 925 may terminate decoding of the signal based onthe first error detection value and the second error detection value. Insome examples, the decoding manager 925 may decode the signal using apolar code to identify the first information value of the set ofinformation values and the second error detection value of the set oferror detection values included in the signal based on receiving thesignal, where determining the coefficient is based on decoding thesignal using the polar code.

The decoding manager 925 may terminate a decoding operation of thesignal before the decoding operation is complete based on determiningthat the first error detection bit is different than the second errordetection bit. In some examples, the decoding manager 925 may decode thesignal using a polar code to identify the first information bit of theset of information bits and the second error detection bit of the set oferror detection bits included in the signal based on receiving thesignal, where identifying the coefficient is based on decoding thesignal using the polar code.

The down-sampling manager 930 may identify a second index value and athird index value based on the index value of the first information bit.In some examples, the down-sampling manager 930 may apply a divisionoperation using a second value to the index value to generate the secondindex value, where identifying the second index value is based onapplying the division operation. The second value, for example, may be adown-sampling factor. In some examples, the down-sampling manager 930may apply a modulo operation using the second value to the index valueto generate the third index value, where identifying the third indexvalue is based on applying the modulo operation. In some cases, thememory stores a down-sampled set of coefficients associated with the setof information bits.

The down-sampling manager 930 may determine a second index value and athird index value based on the index value associated with the firstinformation value. In some examples, the down-sampling manager 930 mayapply a division operation using a second value to the index value togenerate the second index value, where determining the second indexvalue is based on applying the division operation. In some examples, thedown-sampling manager 930 may apply a modulo operation using the secondvalue to the index value to generate the third index value, wheredetermining the third index value is based on applying the modulooperation. In some cases, the memory stores a down-sampled set ofcoefficients associated with the set of information values.

The deinterleaving manager 935 may deinterleave the second errordetection bit from the set of information bits of the signal. In someexamples, the deinterleaving manager 935 may deinterleave the seconderror detection bit from the set of information bits of the signal basedon decoding the signal using the polar code, where identifying thecoefficient is based on deinterleaving the second error detection bitfrom the set of information bits. The deinterleaving manager 935 maydeinterleave the second error detection value from the set ofinformation values of the signal based on decoding the signal using thepolar code.

The power mode manager 940 may be a component of a UE, such as a UE 115,and may enter a lower power mode of the UE based on terminating thedecoding operation. In some cases, the lower power mode is a micro-sleepmode of the UE.

FIG. 10 shows a diagram of a system 1000 including a device 1005 thatsupports error detection for a wireless channel in accordance withaspects of the present disclosure, in particular of any of the previousand following examples. The device 1005 may be an example of or includethe components of device 705, device 805, or a UE 115 as describedherein. The device 1005 may include components for bi-directional voiceand data communications including components for transmitting andreceiving communications, including a communications manager 1010, anI/O controller 1015, a transceiver 1020, an antenna 1025, memory 1030,and a processor 1040. These components may be in electroniccommunication via one or more buses (e.g., bus 1045).

The communications manager 1010 may receive a signal that includes a setof error detection bits interleaved with a set of information bits,identify a coefficient associated with a first information bit of theset of information bits and used for calculating at least one errordetection bit based on receiving the signal, calculate the first errordetection bit based on the coefficient and the first information bit,determine that a second error detection bit received in the signal andassociated with the first information bit is different than the firsterror detection bit calculated using the coefficient and the firstinformation bit, and terminate a decoding operation of the signal beforethe decoding operation is complete based on determining that the firsterror detection bit is different than the second error detection bit.

The communications manager 1010 may also receive a signal that includesa set of error detection values and a set of information values,determine a coefficient, the coefficient associated with a firstinformation value of the set of information values, configured fordetermining at least one error detection value, determine a first errordetection value based on the coefficient associated with the firstinformation value, determine that a second error detection valuereceived in the signal and associated with the first information valueis different than the first error detection value, and terminatedecoding of the signal based on the first error detection value and thesecond error detection value.

The I/O controller 1015 may manage input and output signals for thedevice 1005. The I/O controller 1015 may also manage peripherals notintegrated into the device 1005. In some cases, the I/O controller 1015may represent a physical connection or port to an external peripheral.In some cases, the I/O controller 1015 may utilize an operating systemsuch as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2, UNIX®, LINUX®, oranother known operating system. In other cases, the I/O controller 1015may represent or interact with a modem, a keyboard, a mouse, atouchscreen, or a similar device. In some cases, the I/O controller 1015may be implemented as part of a processor. In some cases, a user mayinteract with the device 1005 via the I/O controller 1015 or viahardware components controlled by the I/O controller 1015.

The transceiver 1020 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 1020 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1020 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1025.However, in some cases the device may have more than one antenna 1025,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1030 may include random-access memory (RAM) and read-onlymemory (ROM). The memory 1030 may store computer-readable,computer-executable code 1035 including instructions that, whenexecuted, cause the processor to perform various functions describedherein. In some cases, the memory 1030 may contain, among other things,a basic I/O system (BIOS) which may control basic hardware or softwareoperation such as the interaction with peripheral components or devices.

The processor 1040 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1040 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 1040. The processor 1040 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 1030) to cause the device 1005 to perform variousfunctions (e.g., functions or tasks supporting error detection methodfor a wireless channel).

The code 1035 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1035 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1035 may not be directly executable by theprocessor 1040 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 11 shows a flowchart illustrating a method 1100 that supports errordetection for a wireless channel in accordance with aspects of thepresent disclosure, in particular of any of the previous and followingexamples. The operations of method 1100 may be implemented by a UE 115or its components as described herein. For example, the operations ofmethod 1100 may be performed by a communications manager as describedwith reference to FIGS. 7 through 10. In some examples, a UE may executea set of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 1105, the UE may receive a signal that includes a set of errordetection values and a set of information values. The operations of 1105may be performed according to the methods described herein. In someexamples, aspects of the operations of 1105 may be performed by a signalmanager as described with reference to FIGS. 7 through 10.

At 1110, the UE may determine a coefficient, the coefficient associatedwith a first information value of the set of information values,configured for determining at least one error detection value. Theoperations of 1110 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1110 may beperformed by a coefficient manager as described with reference to FIGS.7 through 10.

At 1115, the UE may determine a first error detection value based on thecoefficient associated with the first information value. The operationsof 1115 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1115 may be performed by anerror detection manager as described with reference to FIGS. 7 through10.

At 1120, the UE may determine that a second error detection valuereceived in the signal and associated with the first information valueis different than the first error detection value. The operations of1120 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1120 may be performed by an errordetection manager as described with reference to FIGS. 7 through 10.

At 1125, the UE may terminate decoding of the signal based on the firsterror detection value and the second error detection value. Theoperations of 1125 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1125 may beperformed by a decoding manager as described with reference to FIGS. 7through 10.

FIG. 12 shows a flowchart illustrating a method 1200 that supports errordetection for a wireless channel in accordance with aspects of thepresent disclosure, in particular of any of the previous and followingexamples. The operations of method 1200 may be implemented by a UE 115or its components as described herein. For example, the operations ofmethod 1200 may be performed by a communications manager as describedwith reference to FIGS. 7 through 10. In some examples, a UE may executea set of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 1205, the UE may receive a signal that includes a set of errordetection values and a set of information values. The operations of 1205may be performed according to the methods described herein. In someexamples, aspects of the operations of 1205 may be performed by a signalmanager as described with reference to FIGS. 7 through 10.

At 1210, the UE may determine an index value associated with the firstinformation value based on receiving the signal, where determining thecoefficient is based on determining the index value. The operations of1210 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1210 may be performed by a signalmanager as described with reference to FIGS. 7 through 10.

At 1215, the UE may determine a coefficient, the coefficient associatedwith a first information value of the set of information values,configured for determining at least one error detection value. Theoperations of 1215 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1215 may beperformed by a coefficient manager as described with reference to FIGS.7 through 10.

At 1220, the UE may determine a first error detection value based on thecoefficient associated with the first information value. The operationsof 1220 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1220 may be performed by anerror detection manager as described with reference to FIGS. 7 through10.

At 1225, the UE may determine that a second error detection valuereceived in the signal and associated with the first information valueis different than the first error detection value. The operations of1225 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1225 may be performed by an errordetection manager as described with reference to FIGS. 7 through 10.

At 1230, the UE may terminate decoding of the signal based on the firsterror detection value and the second error detection value. Theoperations of 1230 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1230 may beperformed by a decoding manager as described with reference to FIGS. 7through 10.

FIG. 13 shows a flowchart illustrating a method 1300 that supports errordetection for a wireless channel in accordance with aspects of thepresent disclosure, in particular of any of the previous and followingexamples. The operations of method 1300 may be implemented by a UE 115or its components as described herein. For example, the operations ofmethod 1300 may be performed by a communications manager as describedwith reference to FIGS. 7 through 10. In some examples, a UE may executea set of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 1305, the UE may receive a signal that includes a set of errordetection values and a set of information values. The operations of 1305may be performed according to the methods described herein. In someexamples, aspects of the operations of 1305 may be performed by a signalmanager as described with reference to FIGS. 7 through 10.

At 1310, the UE may determine an index value associated with the firstinformation value based on receiving the signal, where determining thecoefficient is based on determining the index value. The operations of1310 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1310 may be performed by a signalmanager as described with reference to FIGS. 7 through 10.

At 1315, the UE may determine a coefficient, the coefficient associatedwith a first information value of the set of information values,configured for determining at least one error detection value. Theoperations of 1315 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1315 may beperformed by a coefficient manager as described with reference to FIGS.7 through 10.

At 1320, the UE may retrieve the coefficient from a memory based on thedetermined index value. The operations of 1320 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1320 may be performed by a coefficient manager asdescribed with reference to FIGS. 7 through 10.

At 1325, the UE may determine a first error detection value based on thecoefficient associated with the first information value. The operationsof 1325 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1325 may be performed by anerror detection manager as described with reference to FIGS. 7 through10.

At 1330, the UE may determine that a second error detection valuereceived in the signal and associated with the first information valueis different than the first error detection value. The operations of1330 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1330 may be performed by an errordetection manager as described with reference to FIGS. 7 through 10.

At 1335, the UE may terminate decoding of the signal based on the firsterror detection value and the second error detection value. Theoperations of 1335 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1335 may beperformed by a decoding manager as described with reference to FIGS. 7through 10.

FIG. 14 shows a flowchart illustrating a method 1400 that supports errordetection for a wireless channel in accordance with aspects of thepresent disclosure, in particular of any of the previous and followingexamples. The operations of method 1400 may be implemented by a UE 115or its components as described herein. For example, the operations ofmethod 1400 may be performed by a communications manager as describedwith reference to FIGS. 7 through 10. In some examples, a UE may executea set of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 1405, the UE may receive a signal that includes a set of errordetection values and a set of information values. The operations of 1405may be performed according to the methods described herein. In someexamples, aspects of the operations of 1405 may be performed by a signalmanager as described with reference to FIGS. 7 through 10.

At 1410, the UE may determine an index value associated with the firstinformation value based on receiving the signal, where determining thecoefficient is based on determining the index value. The operations of1410 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1410 may be performed by a signalmanager as described with reference to FIGS. 7 through 10.

At 1415, the UE may determine a second index value and a third indexvalue based on the index value associated with the first informationvalue. The operations of 1415 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1415may be performed by a down-sampling manager as described with referenceto FIGS. 7 through 10.

At 1420, the UE may retrieve a value from a memory based on the secondindex value, where the coefficient is determined based on the valueretrieved from the memory and the third index value. The operations of1420 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1420 may be performed by acoefficient manager as described with reference to FIGS. 7 through 10.

At 1425, the UE may determine a coefficient, the coefficient associatedwith a first information value of the set of information values,configured for determining at least one error detection value. Theoperations of 1425 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1425 may beperformed by a coefficient manager as described with reference to FIGS.7 through 10.

At 1430, the UE may determine a first error detection value based on thecoefficient associated with the first information value. The operationsof 1430 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1430 may be performed by anerror detection manager as described with reference to FIGS. 7 through10.

At 1435, the UE may determine that a second error detection valuereceived in the signal and associated with the first information valueis different than the first error detection value. The operations of1435 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1435 may be performed by an errordetection manager as described with reference to FIGS. 7 through 10.

At 1440, the UE may terminate decoding of the signal based on the firsterror detection value and the second error detection value. Theoperations of 1440 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1440 may beperformed by a decoding manager as described with reference to FIGS. 7through 10.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the procedures may berearranged or otherwise modified and that other implementations arepossible. Further, aspects from two or more of the methods may becombined.

In the following, several further examples of the invention are providedto facilitate understanding of the aspects of the present disclosure:

Example 1: A method for wireless communication, comprising receiving asignal that comprises a plurality of error detection values and aplurality of information values, determining a coefficient, thecoefficient associated with a first information value of the pluralityof information values, configured for determining at least one errordetection value, determining a first error detection value based atleast in part on the coefficient associated with the first informationvalue, determining a first error detection value based at least in parton the coefficient associated with the first information value,determining that a second error detection value received in the signaland associated with the first information value is different than thefirst error detection value, and terminating decoding of the signalbased at least in part on the first error detection value and the seconderror detection value.

Example 2: The method of example 1, further comprising determining anindex value associated with the first information value based at leastin part on receiving the signal, wherein determining the coefficient isbased at least in part on determining the index value.

Example 3: The method of example 2, wherein determining the coefficientfurther comprises retrieving the coefficient from a memory based atleast in part on the determined index value.

Example 4: The method of example 2, wherein determining the coefficientfurther comprises determining a second index value and a third indexvalue based at least in part on the index value associated with thefirst information value and retrieving a value from a memory based atleast in part on the second index value, wherein the coefficient isdetermined based at least in part on the value retrieved from the memoryand the third index value.

Example 5: The method of example 4, further comprising applying adivision operation using a second value to the index value to generatethe second index value, wherein determining the second index value isbased at least in part on applying the division operation, and applyinga modulo operation using the second value to the index value to generatethe third index value, wherein determining the third index value isbased at least in part on applying the modulo operation.

Example 6: The method of any of examples 4 or 5, wherein the memorystores a down-sampled set of coefficients associated with the pluralityof information values.

Example 7: The method of any of the preceding examples, furthercomprising decoding the signal using a polar code to identify the firstinformation value of the plurality of information values and the seconderror detection value of the plurality of error detection valuesincluded in the signal based at least in part on receiving the signal,wherein determining the coefficient is based at least in part ondecoding the signal using the polar code.

Example 8: The method of example 7, further comprising deinterleavingthe second error detection value from the plurality of informationvalues of the signal based at least in part on decoding the signal usingthe polar code.

Example 9: The method of any of any of the preceding examples, whereinthe method is performed at a user equipment, the method furthercomprising: entering a lower power mode of the UE based at least in parton terminating the decoding.

Example 10: The method of example 9, wherein the lower power mode is amicro-sleep mode of the UE.

Example 11: The method of any of examples 1 to 10, further comprisingapplying an identifier mask to the first error detection value, whereindetermining that the first error detection value is different than thesecond error detection value is based at least in part on applying theidentifier mask to the first error detection value.

Example 12: The method of any of the preceding examples, furthercomprising applying a plurality of identifier masks to the first errordetection value to generate a plurality of candidate values,respectively, and comparing each value of the plurality of candidatevalues to the second error detection value, wherein determining that thefirst error detection value is different than the second error detectionvalue is based at least in part on comparing each value of the pluralityof candidate values to the second error detection value.

Example 13: The method of any of any of the preceding examples, furthercomprising accumulating one or more information values and one or morecoefficients, wherein determining the first error detection value isbased at least in part on accumulating the plurality of informationvalues and the one or more coefficients.

Example 14: the method of any of the preceding examples, furthercomprising identifying a set of information values of the signalassociated with the second error detection value based at least in parton receiving the signal, wherein the set of information values comprisesthe first information value and determining a set of coefficients, eachcoefficient of the set of coefficients associated with an informationvalue of the set of information values based at least in part onidentifying the set of information values, wherein determining the firsterror detection value is based at least in part on the set ofcoefficients and the set of information values.

Example 15: The method of any of the preceding examples, wherein anerror detection value comprises an error detection bit and aninformation value comprises an information bit.

Example 16: The method of any of the preceding examples, whereidentifying the coefficient occurs while the signal is being decodedusing a polar code.

Example 17: The method of any of the preceding examples, wherein thefirst error detection bit comprises a CRC bit.

Example 18: The method of any of the preceding examples, wherein thesignal comprises a downlink control channel.

Example 19: The method of any of the preceding examples, furthercomprising: comparing the first error detection value with the seconderror detection value, wherein determining that the first errordetection value is different than the second error detection value isbased at least in part on comparing the first error detection value withthe second error detection value.

Example 20: The method of any of the preceding examples, wherein thefirst error detection value is determined using the coefficient and thefirst information value.

Example 21: The method of any of the preceding examples, wherein theplurality of error detection values is interleaved with the plurality ofinformation values.

Example 19: An apparatus for wireless communications comprising aprocessor, memory coupled with the processor, and instructions stored inthe memory and executable by the processor to cause the apparatus toperform a method of any of examples 1 to 21.

Example 21: An apparatus comprising at least one means for performing amethod of any of examples 1 to 21.

Example 22: A non-transitory computer-readable medium storing code forwireless communications, the code comprising instructions executable bya processor to perform a method of any of examples 1 to 21.

Example 23: A computer program comprising computer-executableinstructions that, when executed on a computer, cause the computer toperform the method of any of examples 1 to 21.

Although aspects of an LTE, LTE-A, LTE-A Pro, or NR system may bedescribed for purposes of example, and LTE, LTE-A, LTE-A Pro, or NRterminology may be used in much of the description, the techniquesdescribed herein are applicable beyond LTE, LTE-A, LTE-A Pro, or NRnetworks. For example, the described techniques may be applicable tovarious other wireless communications systems such as Ultra MobileBroadband (UMB), Institute of Electrical and Electronics Engineers(IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, aswell as other systems and radio technologies not explicitly mentionedherein.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and components described in connectionwith the disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, a CPU, an FPGA or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, any suitable means adapted to perform therespective functions, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but in the alternative, the processor may be anyprocessor, controller, microcontroller, or state machine. A processormay also be implemented as a combination of computing devices (e.g., acombination of a DSP and a microprocessor, multiple microprocessors, oneor more microprocessors in conjunction with a DSP core, or any othersuch configuration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, any suitable means adapted to performthe respective functions, or any combination thereof. If implemented insoftware executed by a processor, the functions may be stored on ortransmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein may be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that may beaccessed by a general-purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude RAM, ROM, electrically erasable programmable ROM (EEPROM), flashmemory, compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that may be used to carry or store desired programcode means in the form of instructions or data structures and that maybe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of computer-readable medium. Disk and disc,as used herein, include CD, laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an example procedure that is described as “based oncondition A” may be based on both a condition A and a condition Bwithout departing from the scope of the present disclosure. In otherwords, as used herein, the phrase “based on” shall be construed in thesame manner as the phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “example” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, known structures and devices are shown inblock diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person having ordinaryskill in the art to make or use the disclosure. Various modifications tothe disclosure will be apparent to a person having ordinary skill in theart, and the generic principles defined herein may be applied to othervariations without departing from the scope of the disclosure. Thus, thedisclosure is not limited to the examples and designs described herein,but is to be accorded the broadest scope consistent with the principlesand novel features disclosed herein.

What is claimed is:
 1. A method for wireless communication, comprising:receiving, at a decoder, a signal that comprises a plurality of errordetection values and a plurality of information values; decoding, usinga polar code, one or more information values of the plurality ofinformation values received in the signal; determining one or morecoefficients associated with an expected error detection value as partof an error check for the one or more information values, wherein eachcoefficient of the one or more coefficients is associated with aninformation value of the one or more information values; determining afirst error detection value based at least in part on the one or morecoefficients associated with the one or more information values, whereinthe first error detection value comprises the expected error detectionvalue; decoding, using the polar code, a second error detection value ofthe plurality of error detection values received in the signal, thesecond error detection value associated with the error check for the oneor more information values received in the signal; determining that thesecond error detection value received in the signal and associated withthe error check for the one or more information values is different thanthe first error detection value; and terminating a decoding of remainingportions of the signal at the decoder that uses the polar code based atleast in part on the first error detection value and the second errordetection value.
 2. The method of claim 1, further comprising:determining one or more index values associated with the one or moreinformation values based at least in part on receiving the signal, eachindex value of the one or more index values associated with a differentinformation value of the one or more information values, whereindetermining the one or more coefficients is based at least in part ondetermining the one or more index values.
 3. The method of claim 2,wherein determining the one or more coefficients further comprises:retrieving the one or more coefficients from a memory based at least inpart on the determined one or more index values.
 4. The method of claim2, wherein determining the one or more coefficients further comprises:determining, for a first information value of the one or moreinformation values, a second index value and a third index value basedat least in part on a first index value associated with the firstinformation value; and retrieving a value from a memory based at leastin part on the second index value, wherein a coefficient for the firstinformation value is determined based at least in part on the valueretrieved from the memory and the third index value.
 5. The method ofclaim 4, further comprising: applying a division operation using asecond value to the first index value to generate the second indexvalue, wherein determining the second index value is based at least inpart on applying the division operation; and applying a modulo operationusing the second value to the first index value to generate the thirdindex value, wherein determining the third index value is based at leastin part on applying the modulo operation.
 6. The method of claim 4,wherein the memory stores a down-sampled set of coefficients associatedwith the plurality of information values.
 7. The method of claim 1,further comprising: deinterleaving the second error detection value fromthe plurality of information values of the signal based at least in parton decoding the signal using the polar code.
 8. The method of claim 1,wherein the method is performed at a user equipment, the method furthercomprising: entering a lower power mode of the user equipment based atleast in part on terminating the decoding of the remaining portions ofthe signal.
 9. The method of claim 8, wherein the lower power mode is amicro-sleep mode of the user equipment.
 10. The method of claim 1,further comprising: applying an identifier mask to the first errordetection value, wherein determining that the first error detectionvalue is different than the second error detection value is based atleast in part on applying the identifier mask to the first errordetection value.
 11. The method of claim 1, further comprising: applyinga plurality of identifier masks to the first error detection value togenerate a plurality of candidate values, respectively; and comparingeach value of the plurality of candidate values to the second errordetection value, wherein determining that the first error detectionvalue is different than the second error detection value is based atleast in part on comparing each value of the plurality of candidatevalues to the second error detection value.
 12. The method of claim 1,further comprising: accumulating the one or more information values andthe one or more coefficients, wherein determining the first errordetection value is based at least in part on accumulating the pluralityof information values and the one or more coefficients.
 13. The methodof claim 1, further comprising: identifying a set of information valuesof the signal associated with the second error detection value based atleast in part on receiving the signal, wherein the set of informationvalues comprises the one or more information values; and determining aset of coefficients, each coefficient of the set of coefficientsassociated with a second information value of the set of informationvalues based at least in part on identifying the set of informationvalues, wherein determining the first error detection value is based atleast in part on the set of coefficients and the set of informationvalues.
 14. The method of claim 1, further comprising: comparing thefirst error detection value with the second error detection value,wherein determining that the first error detection value is differentthan the second error detection value is based at least in part oncomparing the first error detection value with the second errordetection value.
 15. The method of claim 1, wherein an error detectionvalue comprises an error detection bit and the information valuecomprises an information bit.
 16. The method of claim 1, wherein thefirst error detection value is determined using the one or morecoefficients and the one or more information values.
 17. The method ofclaim 1, wherein the plurality of error detection values is interleavedwith the plurality of information values.
 18. An apparatus for wirelesscommunication, comprising: a processor, memory coupled with theprocessor; and instructions stored in the memory and executable by theprocessor to cause the apparatus to: receive, at a decoder, a signalthat comprises a plurality of error detection values and a plurality ofinformation values; decode, using a polar code, one or more informationvalues of the plurality of information values received in the signal;determine one or more coefficients associated with an expected errordetection value as part of an error check for the one or moreinformation values, wherein each coefficient of the one or morecoefficients is associated with an information value of the one or moreinformation values; determine a first error detection value based atleast in part on the one or more coefficients associated with the one ormore information values, wherein the first error detection valuecomprises the expected error detection value; decode, using the polarcode, a second error detection value of the plurality of error detectionvalues received in the signal, the second error detection valueassociated with the error check for the one or more information valuesreceived in the signal; determine that the second error detection valuereceived in the signal and associated with the error check for the oneor more information values is different than the first error detectionvalue; and terminate a decoding of remaining portions of the signal atthe decoder that uses the polar code based at least in part on the firsterror detection value and the second error detection value.
 19. Theapparatus of claim 18, wherein the instructions are further executableby the processor to cause the apparatus to: determine one or more indexvalues associated with the one or more information values based at leastin part on receiving the signal, each index value of the one or moreindex values associated with a different information value of the one ormore information values, wherein determining the one or morecoefficients is based at least in part on determining the one or moreindex values.
 20. The apparatus of claim 19, wherein the instructions todetermine the one or more coefficients are further executable by theprocessor to cause the apparatus to: retrieve the one or morecoefficients from the memory based at least in part on the determinedone or more index values.
 21. The apparatus of claim 19, wherein theinstructions to determine the one or more coefficients are furtherexecutable by the processor to cause the apparatus to: determine, for afirst information value of the one or more information values, a secondindex value and a third index value based at least in part on a firstindex value associated with the first information value; and retrieve avalue from the memory based at least in part on the second index value,wherein a coefficient for the first information value is determinedbased at least in part on the value retrieved from the memory and thethird index value.
 22. The apparatus of claim 21, wherein theinstructions are further executable by the processor to cause theapparatus to: apply a division operation using a second value to thefirst index value to generate the second index value, whereindetermining the second index value is based at least in part on applyingthe division operation; and apply a modulo operation using the secondvalue to the first index value to generate the third index value,wherein determining the third index value is based at least in part onapplying the modulo operation.
 23. The apparatus of claim 21, whereinthe memory stores a down-sampled set of coefficients associated with theplurality of information values.
 24. The apparatus of claim 18, whereinthe instructions are further executable by the processor to cause theapparatus to: deinterleave the second error detection value from theplurality of information values of the signal based at least in part ondecoding the signal using the polar code.
 25. The apparatus of claim 18,wherein the instructions are further executable by the processor tocause the apparatus to: enter a lower power mode based at least in parton terminating the decoding of the remaining portions of the signal. 26.The apparatus of claim 25, wherein the lower power mode is a micro-sleepmode of a user equipment.
 27. An apparatus for wireless communication,comprising: means for receiving, at a decoder, a signal that comprises aplurality of error detection values and a plurality of informationvalues; means for decoding, using a polar code, one or more informationvalues of the plurality of information values received in the signal;means for determining one or more coefficients associated with anexpected error detection value as part of an error check for the one ormore information values, wherein each coefficient of the one or morecoefficients is associated with an information value of the one or moreinformation values; means for determining a first error detection valuebased at least in part on the one or more coefficients associated withthe one or more information values, wherein the first error detectionvalue comprises the expected error detection value; means for decoding,using the polar code, a second error detection value of the plurality oferror detection values received in the signal, the second errordetection value associated with the error check for the one or moreinformation values received in the signal; means for determining thatthe second error detection value received in the signal and associatedwith the error check for the one or more information values is differentthan the first error detection value; and means for terminating adecoding of remaining portions of the signal at the decoder that usesthe polar code based at least in part on the first error detection valueand the second error detection value.
 28. A non-transitorycomputer-readable medium storing code for wireless communication, thecode comprising instructions executable by a processor to: receive, at adecoder, a signal that comprises a plurality of error detection valuesand a plurality of information values; decode, using a polar code, oneor more information values of the plurality of information valuesreceived in the signal; determine one or more coefficients associatedwith an expected error detection value as part of an error check for theone or more information values, wherein each coefficient of the one ormore coefficients is associated with an information value of the one ormore information values; determine a first error detection value basedat least in part on the one or more coefficients associated with the oneor more information values, wherein the first error detection valuecomprises the expected error detection value; decode, using the polarcode, a second error detection value of the plurality of error detectionvalues received in the signal, the second error detection valueassociated with the error check for the one or more information valuesreceived in the signal; determine that the second error detection valuereceived in the signal and associated with the error check for the oneor more information values is different than the first error detectionvalue; and terminate a decoding of remaining portions of the signal atthe decoder that uses the polar code based at least in part on the firsterror detection value and the second error detection value.